Cirrus Owners and Pilots Association

Simulator Videos: IFR Takeoff Setup

John Fiscus — Mon, 15 Mar 2010 22:54:00 GMT

Sorry for the brief hiatus from posting these videos, things have been busy for us here at The Flight Academy. This is good news, but it doesn't leave me a lot of spare time to indulge my writing habit. Hopefully things will quiet down enough in the near future for me to write more.

I have a couple more videos to post from our recording session last August, I'll put the last up later this week.

In this video set, we're going to demonstrate the way we like to set up our avionics prior to departure for an IFR flight. This is one way of several and I'll comment about some alternatives after the videos. You'll see the setups and hear me talk about why we like to use this method for an IFR departure. In the second part of this video, you'll see what happens when there is a failure and how to deal with it, both inside the cockpit and outside with ATC.

Part 1:

(Please visit the site to view this media)

Part 2:

(Please visit the site to view this media)

Some pilots like to have one of their Garmins on a traffic page, others like to have a Flight Plan page up. I will normally stay in the modes shown in the following videos until I've departed the area since I have a larger concern about losing my PFD when low and busy than I do about knowing the name of my next waypoint. I will normally stay in the modes shown in the videos until I've departed the area since I have a larger concern about losing my PFD when low and busy than I do about knowing the name of my next waypoint.

If you have seen our other videos, you'll remember that we're now offering a program that will allow pilots unlimited access to an instructor and our simulator for a really low price. You can find out more about the program by clicking here.

The short form is that for the price of $3,295 you get all the simulator training and instruction that you want for the year. This is equal to about two and a half days of training so if you could find an excuse to do even that much, you'd be ahead. Spouses are allowed to attend training and take part in a pinch-hitter style course at no cost. We're also working with Starr Aviation Underwriters to offer a 10% discount off your insurance premiums.

Give us a call at (866) 557-1501 or an email at info@theflightacademy.com if you'd like to talk about this program. Don't forget to view our options for people from out of town and some examples of the training you can receive found under the tab along the top titled Unlimited Simulator.

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

CPPP in Vegas: Success in spite of weather

John Fiscus — Wed, 10 Mar 2010 23:49:00 GMT

We had a great CPPP event this last weekend in Las Vegas and I wanted to take a second to say thank you to all who made this event happen.

Thanks especially to all the attendees! Without all of you, none of the rest of us would have been there. It's great to see so many pilots interested in aviation excellence and safety. Keep that kind of mentality and you'll go far in aviation (figuratively and literally).

It was also great to see so many non-pilots attending Mike Radomsky's teaching of the PIC course on Saturday morning and then coming over to the sim so we could put you through your paces. Your dedication to learning about this mode of transportation and specifically how you can help out should the need ever arise shows a high level of responsibility in aviation safety. Be sure to keep practicing with the checklist Mike gave you!

I was able to teach on both days since I was the sim operator for the weekend. If you've read much of my blog over the previous months, you know that we have a full motion Cirrus simulator at our base in Las Vegas. It's a great teaching tool for approaches, procedures, emergencies, and trying out new minimums. I had a great crew of clients come through for their hour and a half or so of sim work. I snapped a couple of photos:

I think Jake knew something was coming:

This is just before the sim session started. You can see the big metal walkways are still down. We pull them up prior to engaging the motion. You can also see TWO fire extinguishers up there. The closer one is real, the one inside the cab has compressed air for fighting the simulated fires I can cause, courtesy of our smoke machine.

I'll see if I can compress the video I shot with my pocket camera that shows the smoke billowing out of the cab... stay tuned.

Thanks again to all who attended. It was a great weekend!

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Tale of a scud runner -- Me!

Rick Beach — Tue, 09 Mar 2010 00:56:00 GMT

Getting home from the Las Vegas CPPP proved challenging for many participants, including me. The weather turned cold and cloudy on Sunday morning and prevented any flight segments. (Thanks to Kelly Rudy for organizing two tours of the Las Vegas TRACON and McCarran tower!)

By 3pm at the end of the CPPP, the weather looked like VFR ceilings would enable me to fly down the Colorado River valley then hook a right along Interstate 10 and end up at Palm Springs to visit family, a flight without ever going into a cold, moist cloud. Fortunately, I wasn’t attempting to get to San Diego, where the terrain would have forced me to climb into the freezing levels in IMC.

As the Chair of the CPPP, one of my last duties involves collecting flight training records from CPPP flight instructors, many of whom commented on my planned departure. Several made skeptical remarks, a couple volunteered weather updates, and one just shook his head.

And as the COPA safety zealot, I’m always acutely aware of the potential headline should I become involved in a pilot-induced accident!

Turns out that I took off, made it about 10 miles south of the dam, turned back and had dinner with several CPPP instructors, who promptly grilled me about my decision process. After the discussion, they encouraged me to add it as an object lesson for other COPA members. Here goes ...

The 5 P’s

Those who have attended CPPP on the west coast know that I often teach the Single Pilot Resource Management session. This scenario-based training module emphasizes the 5 P’s for expanding your situational awareness and practices taking action to mitigate or eliminate risks. Since that’s how I do my flight planning, let me share how I handled this scud running flight. By the way, the 5 P’s are the Plan, the Pilot, the Plane, the Passengers and the Programming.

The Plan (Actually Plural, Plans)

While I don’t teach it this way, in reality my flight planning usually creates several possible alternatives depending on what I expect will happen during the flight. No different this time. And all of this was thought through on the ground before I departed the flight planning room.

Plan A – Fly VFR under the bases

In the Las Vegas area, there were definite ceilings that were VFR, and at each of the airports with TAFs along the way, there were also VFR ceilings. The ceilings had been rising in the afternoon (good) with occasional rain showers (bad) but nothing terribly stormy. Visibilities during the day had been quite good except for the occasional showers. (Insert requisite caution about TAF forecasts being valid for only a few miles around an airport and not for the terrain between airports.)

Plan A was to fly VFR under the bases of the ceilings along the low terrain of the Colorado River valley south from the Las Vegas area towards the Needles VOR and then Parker VOR and then Blythe VOR, but actually following the river. When I got to the Blythe area, I’d find the Interstate and head west towards Palm Springs. Guess I was combining I-Follow-Rivers with the I-Follow-Roads technique!

Furthermore, I would only depart if I had two hours flying time to land about an hour before sunset in the Palm Springs area. I really wanted to see where I was going while under the clouds.

Plan B – No bases, then loiter to see if the weather changes

This weather system appeared to be slowly moving eastward with rain shafts in spots. One of the CPPP instructors even pointed out the rain over the Lake Mead area as I was close to departure. But the radar and the observable weather showed rather spotty areas of precipitation that was shifting around.

Plan B was to loiter in a clear area and see what changed. If it got better soon enough, then back to Plan A, and if not, then onto Plan C.

Plan C – No VFR conditions to continue, then return VFR to Las Vegas

A critical component of my decision making was knowing that COPA had arranged with the hotel to extend the weekend rate to any Cirrus pilot who had to return due to weather. Several people simply never checked out and extended their stays, but we knew that some might try to get out and be forced to return. We offered that out. I knew it and was willing to accept it.

Plan C was to turn around and fly back using the VFR arrival procedure into North Las Vegas (the Cortez arrival from Lake Mead). This made the flight more of an attempt to get to Palm Springs rather than a trip to Palm Springs. For me, that difference is really important.

Plan D – Worst case with no VFR conditions on the return

From talking with Kelly Rudy about Minimum Vectoring Altitudes in the Las Vegas area and watching the freezing levels in the valley, I knew that I’d have the opportunity to climb into the clouds, wait for a pop-up IFR clearance back to North Las Vegas at 4,000 or 6,000 feet, and be able to get back. This was a return and not a departure, so I didn’t need high MEAs to avoid terrain, just modest altitudes to mix it up with LAS arrivals and get to KVGT.

What I didn’t know was how the afternoon temps were cooling off, so I planned to watch the temps as I departed and set my point of no return accordingly.

The Pilot

My flying experience is about 2,800 hours, all but 65 hours in Cirrus aircraft. Most of my trips involve long cross-country legs. I have flown in California for 8 winters, exclusively VFR or VFR-on-Top to see to avoid the cold clouds.

Almost exclusively! This winter differs because of El Nino. The warm ocean currents have created warm winter storms with higher freezing levels, so I’ve twice flown IFR at MEAs that are warm enough to avoid icing.

I acknowledged some fatigue after organizing the CPPP weekend. And the Las Vegas event involved more improvisation than usual!

While I am not a certified instructor, I have taught all of the CPPP ground courses except the avionics modules. That includes the weather courses, engine management and especially the Single Pilot Resource Management course.

And I’ve practiced the 5 P’s technique for 5 years in lots of real-life scenarios.

The Plane

N858CD is an antique SR22, serial number 127, produced in Dec 2001. The engine has 2800 hours since new with a top overhaul at 2200 hours. Engine operation is almost exclusively LOP, using the Big Mixture Pull with 12.5 gph at 9,500 or 15 gph at 5,500 common operating.

Coincidentally, my ARNAV ICDS 2000 MFD is INOP and due for shipment to Sagem for repairs, so I do not have that cool terrain profile view that I like so much, nor a big moving map, nor engine monitoring. However, I have a Sandel HSI with moving map, and two WAAS capable Garmin 430s with terrain databases. Navdata databases are current. Plane is legit for IFR operation, as well as VFR operation.

Onboard weather with a Garmin 496 with XM subscription.

Plane was full of fuel and weight and balance showed a center CG thanks to the two boxes of Cirrus Pilot safety issue in the baggage compartment. Plane equipped with portable oxygen with Oxyarm delivery.

The Passengers

None. No distractions, but no helpers, just me.

The Programming

Flight plan was KVGT - KIDDS - IRISH - EED - P20 - BLH - L64 - L77 - TRM - KUDD @ 3500 feet. Note that I put several airports in the flight plan, both as alternate diversions and to keep my magenta line close to the Colorado River. Altitude preselect was 3500 feet.

Sandel showed the GPS flight plan course line and bearing pointer to the next waypoint, and I used heading mode to meander.

Garmin #1 showed the flight plan with the Colorado River in blue with the Arizona/Nevada state line in dashed white. Map data blocks showed ground speed, time to next waypoint, desired track to next waypoint, and vertical speed rate. Garmin #2 showed the terrain with yellow identifying the terrain less than 1,000 feet below me.

No ARNAV MFD.

iPhone-equipped with Foreflight mobile with VFR and IFR charts for NV and CA, along with AOPA directory.

Also have paper charts for Las Vegas VFR and Low Enroute IFR, as well as paper procedures books for AZ, NV and CA.

What Actually Happened

The Single Pilot Resource Management course recommends reviewing the 5 P’s at several decision points: before leaving the flight planning room, before leaving the ground, every hour en route, before descending, before initiating an approach. Here’s what happened in my flight.

Before Leaving the Flight Planning Room

Looking at the sky gave me some confidence that there was light to see, there was a definite VFR ceiling, and there were some areas of rain to avoid. 5-minute radar showed a band of moisture across my path and satellite view showed a break in the cloud cover opening up where I wanted to go. I got some local guidance on VFR departures. Proceed with Plan A.

Before Leaving the Ground

North Las Vegas ground gave me a VFR departure that would take me north heading 340 to avoid LAS Class Bravo airspace and set up my flight following request. I set the heading in my Sandel and was ready to go.

First Leg to Hoover Dam

Took off from runway 07 and climbed in a left turn to 340 and contacted Nellis AFB. Got radar identification and was given instructions that when reaching 4,000 feet turn heading 090. Ceiling was indeed above me at about 5,000 MSL. And I could see the lake without concern for rain showers. Continue with Plan A.

Nellis handed me off to Las Vegas Approach who cleared me to 5,500. Replied “unable due to clouds, request 3,500”, which was approved. Began my own navigation over the lake towards the dam. Got dropped because I was below radar coverage, squawk VFR, which I had expected.

Had a bit of difficulty figuring out the location of the dam since the channel is hidden from the lake behind some hills. Reviewed my position on the Garmin map with the VFR Terminal Chart. Saw the river below the dam come into view. Saw the new suspension bridge under construction. Saw the dam. Confirmed VFR at 3,500 MSL would keep me under the ceilings and above the terrain. Continue with Plan A.

Beyond Hoover Dam

Meandering along the river was actually fun. Had a great sightseeing view of the river and the surrounding terrain. The Garmin terrain display clearly showed the river valley between areas of yellow, which was terrain less than 1,000 feet below me. Easy to keep myself clear of terrain. Slowed down a bit to 120 knots, partly to ease my maneuvering and partly to enjoy the view more.

Did a wind check to determine the windward side of the canyon. Had learned from the Cory Lidle accident how to use the wind to shorten a U-turn. But needed to choose the correct side of the canyon. Winds were modest 7 knots from the east, directly across my path. Chose to fly along the western edge of the canyon and that gave me a wonderful view of the river from my window.

WINGS intersection

At this point, I encountered clouds down into the valley and blocking my progress. The chart showed WINGS intersection and a slight ridge that was topped with clouds.

Switch to Plan B.

Clouds seemed in motion across the canyon and I was flying in a clear bowl about 1,000 feet above terrain with cloud bases well above me. Decided to loiter a bit and did some figure-8 maneuvers at 100 to 90 knots with flaps 50%. Spent about 15 minutes while watching the clouds change.

Unfortunately, this was the front. The clouds were changing and moving across the canyon as I expected, but new clouds emerged and filled the canyon. Later I learned that the front stalled southwest of Las Vegas, exactly where I was loitering, and simply rotated all night long with clouds, rain in a never ending cycle. I was never going to get past it.

Still had daylight, still had definite ceilings, so switch to Plan C. Flew a U-turn towards the wind and returned to the Hoover Dam and Lake Mead.

Cortez Arrival

As I got to Lake Mead, turned towards Las Vegas and called up approach and requested the Cortez Arrival procedure back to North Las Vegas airport. I was already at 3500 MSL so simply flew the arrival. Weather over Las Vegas had higher ceilings and so enjoyed the flight over the city and wondered who would be available for dinner!

Debrief at Dinner

One of my pleasures of chairing the CPPP events comes from the interactions of so many talented instructors. Made a few calls and arranged dinner with some after checking back into the CPPP hotel. Expected a grilling, and not just my seafood!

First topic of discussion, “So Rick, describe your decision process for this flight?” Couple of comments about the headlines if the COPA safety guru was involved in a scud-running accident. Genuine surprise at my worst-case plan to pop up and return IFR because the MVA enabled it from that area. And encouragement to post this as an object lesson.

Lessons Learned

Personal minimums are personal. They reflect the personal experience levels, risk assessments, risk tolerance, knowledge and skills of the pilot setting the minimums. Each pilot has to determine what minimums are acceptable to them, with their experience, with their proficiency, with their

This is definitely a do-as-I-say scenario. Just because some other pilot did something does not fully explain why they accepted that risk. Hopefully, by explaining my thought process, you can appreciate that a lot of thinking went into hundreds of decisions along the way.

And if you do not fully appreciate how you would handle similar risks, then please do not expose yourself to them.

Cheers 
Rick

FLYING Editors’ Choice Award a Fitting Summary of 2009

Patrick Herguth — Mon, 01 Mar 2010 17:16:00 GMT

This blog post can also be viewed on Avidyne Live.

We were recently bestowed the Editors’ Choice Award for the Entegra Release 9 avionics by FLYING Magazine. This is the third time that Avidyne has won an Editors’ Choice Award for innovations in avionics for general aviation. 2009 was one of the most exciting years in Avidyne’s history and I wanted to reflect briefly on what we accomplished last year.

I think the most important accomplishment for 2009 was our continued focus on our customers. In mid 2008 we committed ourselves to fixing customer service and improving the quality of our products. Last year was about proving ourselves every day to our customers and creating an environment of continuous improvement. We weren’t perfect, but we are proud of the difference we have made in our effort to minimize the downtime of our customers. This will continue to be a focus in 2010 and we have already made some significant improvements in our call workflow to reduce average resolution times from 2 hours to 20 minutes!

Avidyne had a busy year for product introductions. The Entegra Release 9 upgrade leveraged everything we learned from our first generation Entegra products and developed these innovations on the most advanced avionics architecture that you can find in light general aviation. We committed to the market in mid ’08 that we would certify the product within a year and we actually beat that target by several months. This was a tremendous accomplishment by the entire company. We also launched our family of DFC autopilots that can upgrade the existing STEC 55X by swapping the AP flight computer and integrating with the digital ADAHRS in the Entegra avionics system. The EX600 was launched in late 2009 and improved upon the industry leading EX500 MFD and once again delivered new and innovative features to the multifunction cockpit display. Like all of our products, these innovative features were based on a real understanding of how pilots actually use our products. In a year that has been dubbed one of the most difficult in general aviation we were proud to deliver multiple, innovative products to the market.

As a business, we had to transform ourselves with the changing market conditions. Providing high value upgrades to our existing customers is a new and growing segment of our business and one that we feel is appropriate for the economic conditions. More of our customers are keeping their current airplanes, and we are providing them options to improve the safety, utility and simplicity of their aircraft. Our customers have responded to this with over 100 R9 upgrades ordered in 2009 which on an annualized basis was 20% of the total new piston aircraft delivered worldwide in 2009. We are proud of our ability to adjust quickly to the needs of our customers and we will continue to do so in 2010.

Maintenance Préventive

Denis Pariente — Sun, 28 Feb 2010 15:13:00 GMT

Opérer un avion en Novembre c'est se conformer intégralement à la réglementation américaine concernant la maintenance de l'aéronef et ne pas tenir compte du tout de la réglementation européenne. En ce qui concerne la navigabilité et l'entretien de nos avions immatriculés en N nous devons appliquer toutes les règles FAR, rien que les règles FAR.

Il faut bien comprendre que les choses sont différentes en ce qui concerne les règles de navigation, pour lesquelles le plus souvent s'applique la règle la plus contraignante FAR ou JAR (par exemple DME et ADF sont obligatoires pour certaines percées en France même si l'on pilote un avion en N avec une licence américaine), mais c'est une autre histoire...

Ici je ne vais parler que de la maintenance préventive, c'est à dire des opérations qu'un propriétaire d'avion a le droit d'effectuer lui-même sur son avion sans l'intervention d'un mécano agrée. La mentalité américaine est bien différente de la nôtre. S'agissant d'opérations privées (vols non commerciaux) il est donné beaucoup plus de liberté et de responsabilités au pilote américain qu'en Europe.
Cette responsabilisation est source d'une bien meilleure sécurité des vols comme le montrent toutes les statistiques à notre disposition. Se conformer à cette réglementation c'est assurément travailler à notre sécurité et à celle de nos passagers.

La plupart d'entre nous n'est pas mécanicien de formation. Notre formation, notre culture aéronautique nous incitent à être intimidés par la complexité de nos machines. La peur de mal faire, de ne pas respecter la réglementation, de faire des erreurs de procédure mettant en cause notre sécurité et celle de nos passagers nous inhibent pour effectuer des tâches de maintenance nos avions.
Or la FAA nous autorise à intervenir dans de très larges domaines concernant l'entretien de nos machine. Et pratiquer la maintenance préventive de nos avions en routine, nous apporte une grande satisfaction personnelle et nous fait économiser des sommes substantielles. Surtout cette pratique nous permet une meilleure formation et une meilleure connaissance des systèmes de nos avions faisant de nous de meilleurs et de plus sûrs pilotes.
Vous verrez que l'ensemble des tâches d'une révision des 50 heures et de nombreuses autres opérations peuvent être effectuées légalement par un pilote privé américain sur son propre avion. Le pilote consigne lui-même ces opérations sur les livres d'entretien de l'avion et signe l'approbation de remise en service.
Au passage signalons que ces livres doivent être en possession du pilote car leur tenue et la conformité de l'avion sont de la seule responsabilité du commandant de bord, et non du mécano entretenant l'avion...
Ceci est difficile à comprendre pour un pilote français ; pourtant cette responsabilité est explicitement rappelée dans la Section 91.3 (a) des FAR : Le pilote aux commande de l'avion est directement responsable et est l'autorité finale pour les opérations de l'avion. ("The pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft").
Si vous n'avez pas vérifié avant de monter dans l'avion que l'entretien est bien conforme, que les entrées sont bien notées dans le livre et que l'avion est bien navigable ("airworthy") vous êtes le seul et final responsable en cas d'anomalie... Pas le mécano A&P, pas l'inspecteur IA signant la annuelle mais vous, vous au final et vous seul, le Commandant de Bord...
Le pilote n'ayant pas vérifié ces livres avant chaque vol est le seul responsable en cas d'absence de conformité.
En ne gardant pas eux-mêmes les livres d'entretien de leur avion les pilotes opérant un avion en "N" risquent de se retrouver dans la peine. En aucun cas ils ne doivent s'en dessaisir au profit de quiconque, en particulier leur Centre d'Entretien ou tout autre mécano. Ils sont les seuls responsables et l'autorité finale en la matière...

A. Un certain nombre de notions doivent être comprises.

En cas de doute toujours se référer aux FAR-AIM dans lesquels tout est écrit, décrit et prévu et qui ne laissent que peu de place à l'interprétation :

- La maintenance préventive est définie dans le FAR Part 1, Section 1.1, comme les opérations simples et mineures de préservation et de remplacement de petites pièces standards ne mettant pas en cause des opérations sur des pièces complexes ( ".... simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations")

- Pour clarifier cette notion, les FAR Part 43, Appendix A, paragraph (c) contiennent la liste exhaustive de toutes ces opérations établie par la FAA. J'y reviendrai en détail plus bas.

- Un pilote ne doit pas effectuer lui-même ces travaux de maintenance préventive si l'avion est utilisé selon les Parts 121, 127 ou 135 même s'il est propriétaire de l'avion. Ces Parts concernent le transport de passagers ou de fret à titre payant y compris le vol à la demande.

- C'est la Section 43.3(g) qui autorise le titulaire d'une licence de pilote délivrée suivant la part 61, propriétaire ou opérateur de l'avion ("any aircraft owned or operated by that pilot") à pratiquer la maintenance préventive. La Section 43.7 (g) dit que pour pouvoir pratiquer la maintenance préventive sur votre avion vous devez être titulaire d'une licence de pilote américaine. La Section 43.5 interdit les opérations d'un avion sans approbation de remise en service (" approved for return to service"). La Section 43.5 spécifie que les pilotes ne peuvent approuver pour le retour en service que les travaux de maintenance préventive qu'ils ont eux-mêmes effectués.

- La Section 43.7 (a) explique comment doit être rédigée l'entrée dans le manuel de l'avion. Elle doit comporter la description des travaux, la date, le nom de la personne ayant effectué les travaux, le type et le numéro de la licence lui permettant de les effectuer. La signature constitue l'approbation de remise en service ("The signature constitutes the approval for return to service only for the work performed").
Exemple d'entrée dans le livret moteur après changement d'huile :

Date: 02/03/2009; Aircraft: N1234CD; Type SR22; S/N: 281; Hobbs: 1261.1; TTIS: 1261.1

Engine oil change IAW Service Manual Checklist. Drained oil. Removed filter and cut open for inspection.

No metal noted. Installed new Champion CH48109-1 and serviced with 8 quarts AeroShell 15W50. Checked brake fluid and battery levels. Ran engine, leak check OK.

________________________________

Jacques Martin

Owner PP X29XXXXX

B. Les 32 opérations de maintenance concernées.

Regardons cette liste item par item afin de nous faire une idée précise de ce que avons le droit d'entreprendre.

1. Dépose repose et réparation des pneus du train d'atterrissage.
Nécessite de savoir mettre l'avion sur chandelle, de déposer les carénages de roue, de connaître le système de fixation de la roue et le système de freinage.

2. Remplacement des sandows de train d'atterrissage.
Ne concerne pas les Cirrus.

3. Maintenance des amortisseurs de trains hydrauliques ou pneumatiques.
Ne concerne pas les Cirrus.

4. Maintenance des roulements à bille des roues de train d'atterrissage, comme leur nettoyage et leur graissage
C'est tout un art. Bien nettoyer, inspecter les roulements une fois secs et les graisser avec la graisse de grade ad hoc suivant une technique appropriée.
Le must concernant la maintenance préventive.

5. Remplacement de fil à freiner et de goupille de sécurité.
Nécessite le matériel adéquate.

6. Lubrification nécessitant seulement le démontage de parties non structurelles comme les fenêtres de visite, capots, carénages.
La vidange, le changement du filtre à huile font partie intégrante de cet item.

7. Réparation simples sur le tissu d'entoilage.
Ne concerne pas les Cirrus.

8. Faire le niveau du circuit hydraulique.
Utiliser le liquide spécifié par le constructeur.

9. Retouches cosmétiques sur le revêtement du fuselage, de la queue (excluant les gouvernes de contrôle équilibrées), capots, carénages, trains, intérieur cabine ou cockpit sans démonter des parties de structure primaire ou de système opérationnel.
Se procurer la peinture adaptée à ces travaux.

10. Appliquer du matériel de protection et de prévention sans devoir démonter des parties de structure primaire ou de système opérationnel et dans le respect des bonnes pratiques
Un petit coup de WD40 par-ci, de CorrsionX par là ne fait pas de mal. Attention aux alternateurs

11. Réparation de la sellerie, des éléments de décoration de la cabine, du cockpit sans devoir démonter des parties de structure primaire ou de système opérationnel et sans interférer avec un système opérationnel ou affecter une structure primaire.
N'utiliser que du matériel certifié en particulier pour les sièges, garder les papiers de certification.

12. Faire des réparations simples sur les carénages, les trappes de visite non structurelles, les capots, des petits patches ou renforts ne modifiant pas les contours et n'interférant pas sur l'écoulement de l'air.
Pour les Cirrus cet item est utilise pour réparer quelques dommages aux carénages de roue qui sont fragiles. Utiliser le matériel et les procédures approuvées par le constructeur.

13. Remplacer les fenêtres latérales sans interférer avec la structure les systèmes opérationnels tels que gouvernes, circuit électrique etc...
Attention, ne concerne pas le pare-brise.

14. Remplacer les ceintures de sécurité. seulement avec des ceintures et harnais approuvés pour la marque et le modèle de l'avion.
Bien respecter les specs du manuel d'entretien, faire attention au nombre de rondèles etc...

15. Remplacer les sièges ou parties des sièges avec les pièces approuvées pour l'avion sans toucher aux parties structurelles ou système opérationnel
Pas d'improvisation dans ce domaine comme dans celui des ceintures et harnais dont les specs font partie de la sécurité de l'avion.

16. Rechercher la panne et réparer les circuits défectueux dans les circuits de câblage du phare d'atterrissage.
Ne concerne pas les autres circuits lumineux. Pas sûr que la FAA ait pensé à une MCU quand elle a rédigé cet article...

17. Remplacer les ampoules, déflecteurs et lentilles des lumières d'atterrissage et de position.
Concerne aussi les anticollision ("strobes")

18. Remplacer les roues et les skis à condition de ne pas devoir changer la fiche de pesée.
Tout est dit...

19. Remplacement de capots ne nécessitant pas la dépose de l'hélice ou la déconnexion des gouvernes.

20. Remplacement ou nettoyage des bougies d'allumage et réglage de l'écartement des électrodes
Nécessite les clefs adaptées surtout sur les Turbos.

21. Remplacement de toutes les connexions de tuyauteries à l'exception des tuyauteries hydrauliques.
Concerne aussi le chauffage, l'alternate air, l'air frais cabine, la ventilation de l'avionique etc...

22. Remplacement des durites d'essence pré-fabriquées.
Vérifier les agréments de pièce pour l'avion.

23. Remplacement des crépines essence et huile ou des éléments de filtre.
Concerne les filtres à huile, essence et induction d'air. Utiliser les filtres agrées pour l'avion.

24. Remplacer et entretenir la batterie.
Remplacer seulement avec une batterie agrée. Faire le niveau avec de l'eau distillée seulement. Charger la batterie suivant les procédures constructeurs.

25. Nettoyer les brûleur des ballons.
Ne concerne pas les Cirrus non modifiés Mongolfière...

26. Remplacement et réglages des fermetures standards non structurelles secondaires aux opérations
On doit utiliser des fermetures, vis et rivets agrées.

27. Changement des paniers et bruleurs des ballons
Ne concerne pas les Cirrus

28. Installations de détrompeur de remplissage d'essence certifiés par le constructeurs
Ne concerne pas les Cirrus.

29. Démontage, vérification et remplacement des détecteurs magnétiques de particules.
Le bouchon de réservoir d'huile est magnétique sur nos Cirrus. Bien vérifier à chaque vidange qu'il n'a pas pigé des particules métalliques.

30. Les inspections et tâches de maintenance prescrites et spécifiquement identifiées comme taches de maintenance préventive dans le certificat de type d'avion de première catégorie.
Ne concerne pas les Cirrus.

31. Démonter et remplacer les instruments de communication et de navigation auto-contenu dans dans des racks à l'exclusion du pilote automatique, transpondeur et DME.

32. Mise à jour des data bases logicielles des instruments de communication et de navigation à l'exclusion du pilote automatique, transpondeur et DME.

Prenez conseil auprès de votre mécanos, n'hésitez à forcer la porte des ateliers d'entretien, mettez les mains dans le cambouis. Vous vous laverez la tête et sortirez meilleur pilote.
Et quand l'hiver sera fin, votre avion vous emmènera loin.
Fly safe!

Clash of the Titans: Holy Father vs TSA

James Fallows — Thu, 25 Feb 2010 21:58:11 GMT

Maybe this is widely known, but I hadn't heard until recently that Benedict XVI had joined the ranks of critics of the TSA: Details here . Now perhaps I can dare hope for an Encyclical about the inanity of the repetitive "current threat level is Orange" robo-broadcasts, or even a Papal Bull addressing the deeper illogic of today's airport-screening exercise in security-theater. "Your pallium and zucchetto must be off and in the bin. I'm talking to you, sir! All velvet or...(read more)

Bad week in small-plane news

James Fallows — Sat, 20 Feb 2010 03:34:17 GMT

A crash in East Palo Alto two days ago after an early morning take-off apparently in fog, killing three employees of the Tesla electric-car company; the notorious suicide/murder/terror crash in Austin yesterday; a landing in the wee hours this morning at LAX by a 23-year old student pilot who stole a Cirrus SR-22 airplane and flew it erratically all over the place. The stolen plane , Cirrus N443CP*, in happier times: These are completely different situations -- weather-related accident; psychopathic...(read more)

Buzzard Strike (updated)

James Fallows — Mon, 15 Feb 2010 04:30:36 GMT

This is the most bizarre aviation video I have seen in a long time. It was shot in Miami just before the Superbowl, and it shows the results of a bird strike in a helicopter. Bird strikes are unpleasant for all involved, starting with the bird. Small-seeming birds can do an amazingly large amount of damage to an aircraft (cf: " Miracle on the Hudson "). This involves a big bird, and the results are much different from normal for all involved. Thanks to John Tierney of Sense & Nonsense...(read more)

Simulator Videos: Smoke in the cockpit

John Fiscus — Fri, 05 Feb 2010 20:27:00 GMT

One of the best things about simulator training is that we can make all kinds of things happen that we can't even get close to simulating in the real airplane. If you've been following our video series then you've already seen a few of those situations.

In this video, we're going to demonstrate another scenario that most pilots have never experienced this fully: a cabin fire. This is an especially dangerous situation because there's smoke obscuring your vision, fumes obscuring your lungs, and a huge distraction away from flying the aircraft. It's really important that pilots understand the distinction between engine fires and cabin fires (sometimes also called electrical fires) too. It's very common for me to give somebody a cabin fire and the first thing they do is kill the engine. It's a knee-jerk reaction, but if you do it, it'll cost you.

In this video, I'm flying the airplane and Chase Friesen hits me with the fire about 2 minutes after I've departed the airport. He was pretty judicious in his use of the smoke so you'll hear me coughing a few times. The cameras doesn't capture all the smoke due to resolution issues but you'll definitely see traces of it. Suffice to say that it's fairly thick if we want it to be (and Chase wanted it to be... he must have thought I wasn't paying attention).

(Please visit the site to view this media)

The short form is that for the price of 3,295 you get all the simulator training and instruction that you want for a year. This is equal to about two and a half days of training so if you could find an excuse to do even that much, you'd be ahead. Spouses are allowed to attend training and take part in a pinch-hitter style course at no cost. We're also working with Starr Aviation Underwriters to offer a 10% discount off your insurance premiums.

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Simulator Videos: Shooting an ILS Approach

John Fiscus — Thu, 28 Jan 2010 20:51:00 GMT

In this video, we're going to demonstrate the proper procedures for shooting an ILS approach. We'll look at configurations, speeds, and a few common mistakes that we see people make.

I'm using the ILS to 13R at KBFI. If you want to pull up a copy of the approach, you can find it on airnav: http://www.airnav.com/airport/BFI

The sound quality is ok but you'll have to turn your speakers up to hear it all. As these were our first attempts at making videos, we learned a lot about audio and video - our next series of videos are going to be experiments in HD.

(Please visit the site to view this media)

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Langewiesche’s “Silver Chain”

Patrick Herguth — Sun, 10 Jan 2010 13:10:00 GMT

This post can also be found on our Avidyne Live site.

Langewiesche’s “Silver Chain”

I have been working my way through Stick and Rudder: An Explanation of the Art of Flying by Wolfgang Langewiesche and it has been a very interesting read. There are multiple places where Langewiesche talks about making planes safer and easier to fly and he also talks about the idea of a “silver chain” that would keep an airplane from stalling. The thought experiment is that if you put a physical chain on the stick it would never let the pilot pull back far enough to stall the airplane. He debunks the idea because while it would provide a level of safety in some situations, the problem is too complex for this simple design to deliver a plane that wouldn’t stall. I am too much of an airplane novice to understand all of advances in aircraft design that have occurred since the book was published, but I think a lot of the concepts discussed in the book have gone in to making general aviation airplanes easier to fly and more forgiving than the planes he was referencing in the book.

As I thought more about the safety chain concept I realized the envelope protection feature on our DFC90 and DFC100 autopilots is something that Langewiesche would be really happy about. When our autopilot is engaged it acts like the silver chain that Langewiesche realized couldn’t exist as a purely mechanical system. As Mark Krebs explained in his very technical blogs the Avidyne autopilot is constantly running calculations to determine the lift available in the wings of the airplane. This works with any power setting or flap configuration and overcomes the mechanical challenges that hampered Langewiesche’s chain to keep pilots from stalling the airplane during training or in stressful situations.

Envelope protection as a tool during an engine out emergency.

During my primary training last year I spent a lot of time with my instructor practicing engine out emergencies. I have been trying to take to heart the instruction to “fly the airplane” but I found that I barely had enough bandwidth to fly at Vg, pick a landing spot (no CAPS in a 172) and then get set up to put the airplane on that spot. When I was in training mode I did get better at using the GPS to find the nearest airport and I effectively ran through the checklist and “communicated” my emergency. Granted I am still a new pilot, but just flying the aircraft at Vg took most of my bandwidth.

One of the very interesting applications of envelope protection is managing an engine out situation. While cruising the autopilot will most likely be in GPSS mode and holding an altitude. If the engine quits and you do nothing the autopilot will lose airspeed as it tries to maintain altitude. It will do this until the aircraft reaches 1.2Vs and then envelope protection will take over and sacrifice altitude for airspeed. The pilot will have both visual and aural alerts while this is occurring. You can then use the GPS to see if one of the nearest airports is within gliding range and if it is the autopilot can fly direct to the airport. If an airport is not within gliding range then the pilot can use the heading mode for lateral guidance and focus on picking an optimal CAPS deployment or off airport landing spot while the autopilot is doing its job of flying at approximately Vg, not stalling the plane and giving you the most time possible to make the right decisions. Our product management team will work with the instructor community to determine how best to utilize this technology in an emergency situation.

As a new pilot that is still working on my stick and rudder skills I like having this kind of help in the cockpit. The DFC90 and DFC100 can really act like a co-pilot in this situation and allow me to focus on managing the entire emergency beyond just flying the airplane.

Vélo pliant

Denis Pariente — Thu, 07 Jan 2010 01:00:00 GMT

Aller, un peu de pub parfaitement gratuite pour les vélos pliants Brompton.
C'est Mathias Euzen qui nous a fait découvrir ces vélos pliants l'année dernière à Arcachon...

Un des grands plaisir des "incartades" en Cirrus est de pouvoir enfourcher son vélo à l'arrivée, sans rien demander à personne. La sensation de liberté est alors à son comble.
Pour cela il faut trouver un vélo pliant qui puisse entrer facilement dans le coffre de notre avion, répondant à un cahier des charges précis :
- dimension permettant de le rentrer par la porte du coffre Cirrus
- laissant encore de la place dans le coffre à deux de front
- pliable et dépliable en 30 secondes sans aucun effort ni outil bien entendu
- pas trop lourd afin d'être portable et roulable sans efforts
- permettant de se balader en toute sécurité : rigidité, freins, maniabilité
- avec suffisamment de vitesses pour pouvoir être utiliser sur terrain plat, pentu, en ville et à la campagne

Le Brompton est un vrai vélo. Ses 6 vitesses assurent un développement allant de 2.60 à 8 m environ, faisant totalement oublier ses petites roues.
Grâce à son poids et ses vitesses le pédalage est aussi efficace que sur un vélo de route classique, permettant de se balader sur des longues distances sans se fatiguer même si le terrain est vallonné.

Et surtout il est parfaitement dimensionné pour nos avions.
Il rentre par la porte du coffre sans effort

A deux vélos de front dans le coffre, sécurisés par les sangles

Il reste encore moulte place pour les glacières, le pique nique et tout le bazar que nous transportons dans nos avions...

A larrivée il est facile de les sortir de l'avion

Le dépliage est une affaire rondement menée

Fly safe

Simulator Videos: VFR departure briefing

John Fiscus — Tue, 05 Jan 2010 18:44:00 GMT

In this video, I will demonstrate a VFR departure briefing along with a departure which utilizes some of that briefing. It is important that pilots be aware of what they're about to launch into... but many people I train with aren't as ready as they ought to be for anything beyond the norm to happen in those first few seconds of flight. Performing a VFR departure briefing is a good way to prepare for the unexpected ... and ensure the appropriate (and timely) reaction!

As I mention in this video, Mike was able to act quickly and deploy the CAPS when his engine failed right after departure. He could do this because he makes it a requirement to do a departure briefing (not in that video so we could feature it here) and because he uses the "Flaps and CAPS" call every time he departs.

Here you can listen to me perform the briefing and depart using some of those elements:

(Please visit the site to view this media)

A VFR departure briefing is going to be difficult for most established pilots to start performing. I have heard the excuses, but they really boil down to, "I have been flying this long and it works fine. I know what to do if something happens, I can handle this." Of course we think we could handle it. If we didn't, then why climb into the airplane in the first place? That wouldn't be very smart...

But what we find when doing simulator training is that many pilots aren't all that prepared to make a tough call fast. A pretty hefty margin of experienced Cirrus pilots don't make the decision to pull the CAPS handle soon enough, espeically when there's something like a low altitude engine failure involved and time is short. After a few scenarios in the sim, we find those habits changing quickly.

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Destination $100 Hamburger : Beaune

Denis Pariente — Sun, 27 Dec 2009 15:45:00 GMT

Ce 26 décembre la météo parait très favorable. Notre N842CD n'a pas volé depuis 2 semaines, il nous faut donc faire chauffer l'huile, charger la batterie et désoxyder les appareils électroniques.
C'est décidé nous irons passer la journée à Beaune...

La destination parait correspondre parfaitement au cahier des charges : tout juste 1 heure de vol à partir de Toussus, une piste en dur de plus de 1000 m de longueur et une ville médiévale à moins de 10 mn en vélo, dont les Hospices et ses ventes sont mondialement connus.
La destination €100 hamburger parfaite .

Nous ferons le vol aller en VFR et compte tenu de l'heure du coucher du soleil, le retour en IFR, régime Z, de nuit.
Avant de partir je prépare donc le plan de vol retour.
Le dépôt se fait en 2 étapes et moins de 3 minutes grâce aux 2 outils indispensables au pilote IFR européen : FlightPlanPro et HomeBriefing.

1. Sur FlightPlan Pro il suffit de rentrer le départ en VFR (en rouge), la destination et le niveau de vol et appuyer sur "Autoroute" :

Le programme trouve la route tout seul et la valide sur le site du CFMU : 1 minute et demi

2. Un copier/coller de cette route dans le menu "Importer Plan de Vol" de HomeBriefing :

Encore 3 cliques de souris et une minute et demi ;le plan de vol est passé...

Le vol aller en VFR se fera entre 1500ft et 2500 ft QNH. Pas très moin du sol quoi.
Nous nous régalons à la vue des vaches, des châteaux, des collines se dissolvant dans la lumière blafarde du solstice d'hiver.

Paysages en négatif, où les ombres portées sont blanches du givre qui persiste à l'abri du soleil :

Bizarre ce château, cimetière d'avions à Savigny les Beaunes, juste avant d'arriver. Quelqu'un connait ?

Après l'atterrissage, hop les vélos ! Et nous voila partis.

Beaune est une ville médiévale recroquevillée derrière ses remparts et ses richesses vinicoles.
Capitale des vins de Bourgogne, elle est entourée par de multiples villages aux noms évocateurs : Pommard, Meursault, Pernand-Vergelesses, Puligny-Montrachet. A voir : vieux pavés, tuiles de Bourgogne, Hospices, Basiliques et bien sûr caves séculaires à tous les coins de rue. Tout ça dans une ambiance festive de vacances de Noël

Nous somme raisonnables et ramenons un Nuits Saint Georges 1988, année de mon brevet de pilote

Il est bientôt l'heure repartir, le soleil se couche à 16h58 locale

Il fait déjà nuit à Dijon quand nous passons en régime de vol IFR

Ambiance sur le Morvan ! Le soleil n'en finit pas de se coucher

A l'arrivée Paris comme une offrande en forme de rivière de diamants...

Fly safe!

Simulator Videos: Engine failure after takeoff - CAPS save

John Fiscus — Fri, 18 Dec 2009 21:00:00 GMT

Here's the third in our video series about what you could do if your engine fails shortly after takeoff. In the last videos (found here and here) we first looked at what would happen if the pilot attempted to return to the airport, with disastrous results. Next we tried to land straight ahead in a field and while that worked a little better, it was clear that this doesn't have a great chance if you're departing in a place where there's any kind of ground clutter around.

In this next video, we'll have Mike perform the wisest of the 3 options: he'll use the Cirrus Airframe Parachute System after a quick attempt to get the engine back online:

(Please visit the site to view this media)

This is scenario is one that offers pilots very little time to react. If Mike didn't know his engine failure checklist by heart, he'd have spent too long trying to do that and lost too much altitude for the parachute to be a viable option. If he hadn't been trained to use the chute quickly, he may also have missed the window.

Would Mike have survived? I think we have enough data from low altitude parachute deployments to say that he has a pretty good chance in this scenario. So long as he uses the CAPS option above 500 feet (his engine failed at 700 feet) and is in normal controlled flight (not falling rapidly), then he's probably going to walk away. The airplane is totaled, but that should be the last consideration in a situation like this. Machines and money are temporary and replaceable. You aren't.

My next video will be featuring a VFR departure briefing procedure, I'll post that next week

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Simulator Videos: Engine failure after takeoff - land straight ahead

John Fiscus — Thu, 17 Dec 2009 18:11:00 GMT

Here's the second in our video series about what you could do if your engine fails shortly after takeoff. In the last video (found here) we looked at what would happen if the pilot attempted to return to the airport, with disastrous results. Turning back to the airport is generally a recipe for disaster below an altitude of even 1,500 feet - and that all depends on how steeply the pilot climbs out. If you climb shallow (and speed away from the airport), the required altitude might be even higher than that.

In this next video, we'll have Mike attempt to land straight ahead but in a congested area. There are trees, buildings, and roads but not too many great options. He'll make do with what he's got. Have a look:

(Please visit the site to view this media)

As you could see, landing straight ahead is a little better than trying to turn back... Mike chose to land in a field next to the river off his nose. There was a road off to his right but it wasn't very straight at all and that was pretty much it. There were numerous things in the field which made it less than a perfect place to land: ditches and holes. The aircraft in this case rolled over when the left main collapsed, bounced into the air, and then continued to roll over and come to rest inverted.

Would Mike have survived? There's a fair chance of that. I'd say there's a very low chance that he'd have survived unharmed, but I don't think it's necessarily a death sentence. He'd probably be walking with a limp for the rest of his life, at least. The airplane is surely totaled and he's likely going to need help getting out of the inverted aircraft. If there's a fire, the risk to his life goes up even more.

I hesitate to put a clear percentage chance to his survival simplly because that kind of analysis isn't plausible. I think we could easily agree that hitting a ditch and rolling the airplane, even at stall speeds around 60 knots, would not end well in most cases.

I'll post the next video in this series which explores the options that most don't choose, at least the first time, but is the most survivable of the three.

If you saw the last video, you'll remember that we're now offering a program that will allow pilots unlimited access to an instructor and our simulator for a really low price. You can find out more about the program by clicking here.

Safe flying!

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

More on frolics and other language points

James Fallows — Tue, 15 Dec 2009 04:34:20 GMT

I mentioned recently the odd use of the term "frolic" in the FAA's complaint about the pilots who "forgot" to land in Minneapolis, and also my friend Cullen Murphy's exercise in writing an entire article in "E-Prime," a form of English that excludes "is," "are," or any other form of the verb "to be." Illuminating comments from readers on both points below: one in derogation of the skills of the FAA letter-writers, the other in praise...(read more)

Simulator Videos: Engine failure after takeoff - return to airport

John Fiscus — Mon, 14 Dec 2009 20:36:00 GMT

At The Flight Academy, we've been fortunate to have one of the 3 full motion Cirrus simulators to enhance our training abilities. A few months back, Mike Radomsky installed 4 closed-circuit cameras into our rig and that made Luke and I think about how we could use the sim in other ways than just one-on-one training. We decided to write up some scripts and make a few training videos.

Over the next few weeks, we're going to post those videos. This first week, we're going to post a total of 3 videos showing the possible outcomes of an engine failure right after departure. Number one will be what you should never do, which is try to return to the airport. If you don't see the "full screen" button on the lower right of the video, just double click on it to go to YouTube's site. You should be able to make the vid full screen there. Have a look:

(Please visit the site to view this media)

After this week, we'll be posting videos about all manner of VFR and IFR flying - both normal and emergency situations.

Simulators are great for a lot of reasons. They allow us to create a situation that is realistic, remove or add distractions, and allow a situation to go all the way to the end... whatever that may be. What's more, this is one of the few places you can pull the CAPS handle as a response to an emergency. Our data shows that most pilots won't do that when it counts the first time... and after one or two more scenarios that begins to change.

We'd also like to announce that we're going to offer a program that will allow pilots unlimited access to an instructor and our simulator for a really low price. You can find out more about the program here: http://theflightacademy.com/simulator/unlimited-intro.html The short form is that for the price of 3,295 you get all the simulator training and instruction that you want for a year. This is equal to about two and a half days of training so if you could find an excuse to do even that much, you'd be ahead. Spouses are allowed to attend training and take part in a pinch-hitter style course at no cost. We're also working with Starr Aviation Underwriters to offer a 10% discount off your insurance premiums.

Check in for our next video later this week!

Safe flying,

John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

If you've been wondering about NW flight 188

James Fallows — Fri, 11 Dec 2009 22:52:42 GMT

That's the one that "missed" Minneapolis, overshot by 150 miles or so, then did a U-turn over Wisconsin before returning for a safe landing. Afterwards the two pilots said they had been "distracted" by a discussion about new scheduling software on their computers and therefore just didn't notice that they were out of touch with air traffic controllers for 90 minutes. The FAA, in no-nonsense fashion, soon revoked the pilot certificates for both men. The always-informative...(read more)

Speaking Fluent WAAS: Part 4

John Fiscus — Mon, 07 Dec 2009 18:49:00 GMT

Here's the 4th and final video in our Speaking Fluent WAAS seminar. Let us know what you think!

(Please visit the site to view this media)

Safe flying!

-John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Avidyne DFC 90 & DFC 100 Autopilot: Envelope Protection

Patrick Herguth — Mon, 07 Dec 2009 18:09:00 GMT

This post was written by Mark Krebs, our Vice President of Engineering for Guidance and Controls and can be found on our Avidyne Live site

Envelope Protection

"Envelope Protection" is the name we give to two autopilot features that work to prevent stall and overspeed. In this post I'll discuss only the stall prevention part.

Considering how an autopilot works can easily become an exercise in flight dynamics. Fortunately it's a familiar topic for pilots! We'll introduce some of the mathematics along the way, and I think that whether you like math or not, you'll be able to connect your piloting knowledge to the equations.

Flying can be thought of as a hierarchy of decision making. Naturally you want to keep the airplane right side up, a very tactical consideration. You also want to avoid weather and traffic, achieve and capture an altitude, prevent stall, and, eventually, get there! And you more or less want all those things at the same time. A human's actually a pretty impressive computing machine, and the prioritization humans do almost unconsciously can be tricky to program.

Following the human model just described, the autopilot treats envelope protection as one of several simultaneous objectives. Like you, it wants to control pitch, limit g's, achieve commanded rate of climb & etc all at the same time. We employ two general techniques to get this done in the DFC series autopilots, one of them a little bit unusual...

First, and conventionally, many commands can be met while while constraints are simultaneously applied elsewhere. For example, upon encountering the glideslope, the AP will try to pitch over and capture it subject to the constraint that the g factor not drop too low. This is pretty easy thing to implement; somewhere in the autopilot there's a signal that represents the g load on the airplane. That value gets first calculated as a command by the glide slope control loop and then passed on to other functions for checking. One of those functions is the g limiter: whatever the REST of the autopilot would like to do, g's are constrained to the range of 0.2g to 3g. Once g command is determined, the next function down the line figures out how to achieve those g's using elevator servo commands.

I have used this as the first example because you do the same thing when you are flying. Your arm is the servo in a feedback control loop, pulling harder when you want more load factor from the airplane. The feedback comes from your body, which can measure g a couple of ways.

So, the constraints are relatively easy to understand as limitations applied to whatever else you want to do. Multiple competing objectives are a little more difficult to implement in software, but they're still easy enough to understand. For instance, given a vertical speed command, an altitude target, and "don't stall" as simultaneous mandates, whatyou do is prioritize them. "Don't stall" is most important, then vertical speed, and finally the altitude command is the last priority. What the DFC90/100 does, (and perhaps what you do too, if you think about it) is run these control loops at the same time, one for altitude hold and one for vertical speed. This is the second, and more unusual technique I mentioned above.

For contrast let's briefly consider the conventional approach. The AP could use various mode transition criteria to switch between loops, and only run one control loop at a time. That's common practice, however you can often feel a mode switch happening in those other autopilots, or notice that the switch didn't happen at the right time. Avidyne does not do it that way for critical pitch loops.

These loops are like two distinct imaginary pilots, competing for stick time. Perhaps the altitude autopilot is trying to point steeply up because the altitude command is 5000 feet above the present altitude, way up there! Meanwhile the other one, the VS control loop, is perfectly happy holding 800 feet/sec and wants to keep pitch right where it is at 7 deg. The prioritization logic chooses VS over altitude and now it's clear why: it would be crazy to use the altitude loop while we're still 5000' away from the command. The very reason there's a climb loop is that the altitude hold algorithm is so particular that, in responding proportionately to the very large altitude discrepancy pertaining during a climb, it would always be calling for an unsustainable aircraft maneuver: "Oh my gosh we're 5 THOUSAND feet off altitude, point the nose straight up!"  Instead the climb loop overrides the altitude loop until the aircraft reaches a height where it can respond linearly to command inputs based on altitude error.

What then controls the Avidyne autopilot's hand-over logic, and how is it different? Well, since we're running all the loops all the time, we can compare them. The capture transition happens at precisely that moment when the two control algorithms agree on the pitch command. That way it's perfectly smooth handover every time. This is a helpful way of thinking about the different modes too; that they are all "in there" somewhere, active all the time, computing and offering their elevator servo command to a supervisory function which selects from between the competing inputs. Now imagine that one of these behind-the-scenes autopilot controllers is concerned only with lift. It's not thinking about thevertical speed, or the altitude or the pitch angle or anything else: just lift. With that foundation, we are now in a good position to understand envelope protection.

Stall prevention is just one more control loop that's running all the time. It works in the background, and generally has high tolerance for whatever else the AP wants to do. However, the stall prevention algorithm has the absolute last word and it may take over the "pitch rate control loop" at any time: it's never switched off. Now, pitch rate is the innermost heart of the autopilot, analogous in humans perhaps to the subliminal "thinking" that keeps you balanced while walking, or when you’re flying an airplane, manages the g loading.

The metaphor isn't far fetched either, because there is an exact relationship between the autopilot's control of pitch rate and your control of g loading. It's called speed. The equation a = w x V_tas is unavoidable here. The variable w represents pitch rate¹ and a is the kinematic acceleration meaning the motion that results from the g forces applied to the aircraft. So we see that g's are proportional to pitch rate, and their ratio is speed. This is the centripetal acceleration equation from high school physics. Of course, there is one more component of the g's you feel, and that is the one g of gravity. We all understand the underlying concept perfectly well: it takes lift to fight gravity and it takes still more lift to turn the airplane, and you feel both of those in the seat of your pants as g loading.

At this point we have outlined almost all the computations that have to happen. The last one is a possibly familiar lift equation: Lift = 1/2 S_ref * rho_SL * Vias² * CL.² In words, the wing can generate lift in proportion to indicated airspeed and lift coefficient (CL) which you control through the angle of attack. We know we can not a exceed well defined maximum lift coefficient, called (no surprise) CL_max. Try to use more angle of attack and the stall buzzer goes off as you approach flow separation. So maximum lift is known. Further, lift and g are related by mass and we know earth's g is 32.2'/sec² so subtracting those (Lift_max - m*g) tells you how much extra lift is left over. That surplus lift can be used for acceleration, to turn the plane and that's pitch rate. It's important to mention the difference between kinematic and measured acceleration. Because of gravity you measure one g of acceleration even when you aren't kinematically moving at all. So what you (and the accelerometers inside the AHRS) feel is the vector difference between kinematic acceleration and g: a_meas = a_kine - g³. Since this is a vector equation, a lot of trigonometry arises as soon as we depart from zero pitch and roll, but for now if you will just stipulate that the geometry is properly accounted for, we can imagine that a fixed Lift budget gets“spent” on counteracting gravity and generating pitch rate.  If there's not enough lift because we're going too slow, then we either can't turn or can't fight gravity or both, you pick. The autopilot does this math and reduces things accordingly, starting with bank (limiting turns) and then grudgingly constraining pitch rate too. It is by controllling pitch rate that we limit g, hence lift.

What's interesting here is all the things we didn't have to consider here. There is no mention of vertical speed, or altitude, or airspeed control, or even pitch. Those are all important but do not matter to the equations implementing stall prevention. The algorithmthat's running behind the scenes is: "calculate the lift, subtract gravity, see what's left to accelerate the aircraft and then don't allow the pitch loop to try any harder than that." That might mean the calculated pitch rate comes out negative: you can fly slower than stall speed if you're willing to pitch over while doing it!  Finally, to be conservative, envelope protection always assumes max weight, just like the colored arcs on your airspeed indicator.

That completes the discussion of this envelope protection. The key points are that it’s always there in the background, calculating lift and keeping the airplane from approaching stall. You should never hear the stall buzzer while your DFC autopilot or flight director is engaged. (Well, providing you’re following the flight director.)

notes

¹w is the greek symbol for angular rate of rotation, a vector including not just pitch but roll and yaw rate as well.

²Here I must use the programmer's * to denote multiplication because later I will need "x" for the vector cross product.

³The bold font means these are vectors, and kinematic is construed to mean "in consequence of motion.

Another gift possibility

James Fallows — Sun, 06 Dec 2009 20:49:39 GMT

In the Atlantic's special on-line "Editors' Choice" gift guide , I aim very high with my own wish-list item, on the principle of "if you don't ask, you'll never know." But in case you're not quite motivated to get me that item (a flying boat), a nice second choice would be the completely solar-powered airplane that took its first flight in Switzerland this past week . Note: the opening scenes in the video below, which show the plane soaring over the Alps, are...(read more)

Speaking Fluent WAAS: Part 3

John Fiscus — Fri, 04 Dec 2009 17:23:00 GMT

This is the 3rd in our 4 part video series. Thank you all for the feedback and letting me know you've seen these! Luke and I plan to make more.

Also, we're finishing the editing on our first try at videoing some lessons in our full motion simulator. Keep checking back, I expect to start posting those videos in about a week. We have a total of 8.

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Safe flying!

-John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Speaking Fluent WAAS: Part 2

John Fiscus — Thu, 03 Dec 2009 00:11:00 GMT

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Safe flying!

-John Fiscus

Chief Pilot, The Flight Academy

www.theflightacademy.com

Gift thoughts for the holidays

James Fallows — Tue, 01 Dec 2009 10:38:23 GMT

I am a fan of nearly every kind of small aircraft, but I might draw the line here: It's a personal helicopter, really two rotors on a hat. Action video here , from Makezine (thanks to Dave Proffer). As it happens, one of my upcoming New Year's resolutions is to get back into aviation actively. But avoiding this hat-helo would be consistent with two of my rules for a happy flying career: Don't fly anything that's not factory-built (sorry, home-crafters ); and fly only airplanes, not...(read more)