It’s some time since I read the attached, and perhaps there is a more comprehensible NTSB style report, but a propos the hour builder thread, it would be interesting to get the high altitude, jet pilots to comment on the unreliable airspeed actions, high altitude stall actions and loss of control actions and how they mesh in type rating and recurring simulator training.
http://www.vanityfair.com/news/business/2014/10/air-france-flight-447-crash
MCC courses are, as it says on the tin, procedural, call out type courses for multi crew. JOC (Jet Orientation) may provide some high altitude handling familiarisation if the simulator is up to it – I have a feeling a lot of JOC sims may not provide much fidelity, unless they are high end, type rating, full motion sims.
Unreliable airspeed is typically a memory item, and above FL100 might require CLB power and 5 degree pitch up, which conflicts with stall recovery, at least in part.
I find it hard to believe the AF crew were so devoid of basic handling skills, and there must be other context, cognitive reasons for the tragic outcome.
In the same way US society requires an ATP for Part 121, it is good, in my opinion, that they will also require formal upset training, with all the appropriate ground theory training to ensure the various failure paths are recognised correctly.
I read it quite some time ago, it’s quite thorough.
RobertL18C wrote:
Unreliable airspeed is typically a memory item,
On the type I fly it is not a memory item. There are three independent airspeed indicators and a FMS driven ground speed indication. Plus two groundspeed indications from our EFBs (ipad) and if necessary two more from each pilot’s mobile phone. If one really can’t work out a realistic airspeed from those indications, then there is an AoA indicator as last resort. Should that one fail as well (as it would in case of a total electrical failure) hold a typical pitch attitude for cruise and set the power to a typical figure for cruise. Which in case of a total electrical failure is not an easy task because all the engine instruments are electrical…
Martin thank you for the link. It has a lot of interesting precedents for unreliable airspeed events.
Modern glass de clutters the PFD when you exceed parameters, in addition to activating the pusher. Will have to learn how these protections were overridden by humans.
Unreliable airspeed and airspeed mis compare events are memory items on the Airbus family, I believe, and the BEA report mentions the recovery actions
what_next wrote:
If one really can’t work out a realistic airspeed from those indications, then there is an AoA indicator as last resort.
An acquaintance of mine used to fly heavy cargo (IL-76, if I remember correctly) in places where exceeding MTOW was more of a rule than an exception. He said they were essentially using the AoA indicator instead of the ASI even in routine operations.
Not a memory item on the Mustang but like what_next we have two pitot systems and three airspeed instruments. Procedure is to compare all three and find the two that match. Then compare to pitch and power and discard the one that seems wrong. I also have the Garmin GDL39-3D with its own AHRS and GPS speed.
In a complete electrical failure (including no battery power) I am also somewhat stuffed. Would have to fly off standbys and use ipad etc for speed if standby ASI was wrong (pilot’s side pitot blockage for example). At least the FADEC would keep the engines running….I have FADEC detents so at least setting cruise power is easier for me.
Typically at the corporate aircraft level one channel of the ADC/Pitot feeds the Pilot PFD, while the other channel feeds the co-pilot PFD and the ESIS. In effect you may only have two airspeed sources?
The AoA vanes and dynamic speed bugs are also affected by ice related failure events.
Reaching an understanding of the failure paths for each glass system seems to be the reward of hours of study, then when you switch to new glass and the process starts again.
RobertL18C wrote:
Typically at the corporate aircraft level one channel of the ADC/Pitot feeds the Pilot PFD, while the other channel feeds the co-pilot PFD and the ESIS. In effect you may only have two airspeed sources?
In ours the left pitot feeds ADC1 (which is used by default for the pilot’s PFD) and also supplies the standby instruments. The right pitot feeds ADC2 (by default the co-pilot’s PFD). Obviously the PFD’s can be selected to use the other ADC if needed. Our AoA vane only provides a Vref bug on the speed tape not an actual AoA measure so would be less useful.
JasonC wrote:
I have FADEC detents so at least setting cruise power is easier for me.
On our aircraft the cruise detent can result in exceeding Vmo/Mmo. Definitely the case at low altitude
RobertL18C wrote:
Typically at the corporate aircraft level one channel of the ADC/Pitot feeds the Pilot PFD, while the other channel feeds the co-pilot PFD and the ESIS. In effect you may only have two airspeed sources?
This may be one of the differences between Part 23 and Part 25 (would have to look that up for confirmation). “My” C560 is Part 25 (transport category) certified and has three independent pitot-static systems and three independent air data computers. The standby instruments have their own independent battery, while their pitot heater is wired to the emergency battery bus. And since it is a straight-wing aircraft it has plenty of margin between stall and overspeed at almost every altitude. Maintaining neutral pitch and moving the power levers anywhere near the middle of their travel will result in a safe and stable flying condition. Therefore, “unreliable airspeed” is one of my minor worries…
