Manual Feathering before Acceleration Altitude (TURBO-PROPS)

[1jz]

Just a reference required;

If in a turbo-prop an engine fails at takeoff and the auto feather function doesnt feather the prop, this will for sure increase drag and if its high elevation, high temperature and high pressure altitude with max takeoff weight then its improbable to achieve the required amount of climb gradient and the aircraft controllabilty is also effected adversely.
logically with proper identification the prop can be feathered..
I just need your help to locate any such 'manual feathering procedures before acceleration altitude' on whatever type, that are being used in any company and are approved by relevant civil aviation authority (FAA,CAA or T.Canada etc)
thanks

[multis81]

On ATRs and my company say that in the event of an EFATO that fails to auto fx, pm will identify, pf will verify and prop will be fx by means of condition lever. No further actions until acceleration alt.

Will pm you with a scan of the pages tomorrow if you like?

Hope that helps

[1jz]

thanks multis81 that would be appreciated... thats what i was looking for.

[Tu.114]

On the DH8, in case of an engine failure after V1, the affected propeller is triply feathered.

Whenever such a thing happens, it triggers memory items. Firstly, maximum takeoff power is set on the good engine, then the absence of a fire warning and the correct working of the autofeather system is verified. If it has done its job (and no fire is indicated), there is no further action until acceleration and cleanup is completed. If however the autofeather has not worked for some reason and the propeller is still running at windmilling speeds (about 200-300rpm), the memory items continue with a full shutdown of the affected engine; this contains two other attempts at feathering the propeller. Firstly, the power lever goes to flight idle, then the condition lever will go to Fuel Off (#2 attempt at feathering). Whether or not this has worked, the Alternate Feather switch will be selected thereafter (#3 feathering attempt).

After that, there are only very few freak failures that can leave the propeller unfeathered - some blockage/rupture of the oil passages in the governing mechanism maybe. But nevertheless, it is well possible to fly a DH8-400 with an unfeathered failed engine and even coerce it to climb at a low rate. One can compare the climb performance of a -400 in this situation to that of a -300 with the failed engine properly feathered. The -300 is a wholly different beast though; there always was a lot of fun in the simulator when the PNF only casually proceeded to feather the dead engine.

[THE ORACLE]

Hi 1jz,

A further comment. Simulator based transport category turboprop training and rating renewal programs generally include a sequence where after an EFATO either the prop fails to feather or autocoarsen (depending on the make of propeller), or after feathering/autocoarsen has occurred a further simulated failure of the autofeather/autocoarsen computer is introduced resulting in the propeller unfeathering on the failed engine.

Either scenario could also incorporate an engine fire and the distinction is determined by the pilot monitoring (PM) with a standard call response of "engine failure", "engine failure and fire" or "engine fire" (when a fire warning is triggered but no corresponding power reduction is indicated on the affected powerplant). In response the pilot flying (PF) will call for the appropriate memory items, which after confirmation (by the PF) the PM will action.

Generally these scenarios are conducted in a night environment to train/ensure pilots use their instrument scan to remain within the surveyed runway environment while rectifying the problem and either type of problem will result in a rapid deterioration in climb performance until the prop is feathered.

Many transport category turbos have an APR (Automatic Power Reserve) function that is triggered when the system detects a reduction in certain engine parameters below a range of "normal" thresholds (which the system recognises as a failure) and correspondingly it boosts power on the live engine by 7 to 10 percent (depending on the make of engine) whenever this occurs.

After the initial memory items are completed to manage such a scenario, there may also be a supplementary memory item if the propeller fails to feather after the condition lever is moved to fuel OFF, which then requires the autofeathering/autocoarsen system to be switched OFF in order to ensure the failed system s 'locked out' and cannot send any signals to the power plant that could cause further erosion of performance.

Generally the sequence of memory items (and this can vary depending on the make of powerplant and propeller combinations) is, power lever reduced to 20 to 30 percent (min drag position for some powerplant/prop combinations - rather than flight idle), condition lever - fuel OFF, if the prop doesn't feather at this point - autofeather/autocoarsen system OFF, manual feather pump (for the corresponding powerplant/prop) ON until the prop feathers (which depending on the type of prop can take from 5 seconds up to 30 seconds), although it is usually quite quick due to the air load already acting on the windmilling prop.

If the manual feathering pump is required to be used the live engine power lever must then be advanced without delay, as the procedural switiching OFF of the autofeathering/autocoarsen system will also disarm the APR function (mentioned above), resulting in the loss of that vital extra 7 to 10 percent of torque, which must be restored immediately to assist with further climb through the aircraft acceleration altitude.

The Oracle

[rigpiggy]

most FAR23 T-Props use Auto feather systems to allow a higher TGW. A malfunctioning AFX system, grounds the aircraft, and requires a ferry permit.

[1jz]

@ Tu.144 thanks for the info, thats really the type of stuff i might need for reference, do u have any approved document that states all this?

@ THE ORACLE
thats very good info, the aircraft i fly has an auto uptrim n auto feather system in case of an efato but, i m just looking for material that is approved by the relevant authority and allows the crew to manually feather before reaching the acceleration altitude in case auto fx fails.

@rigpiggy
i appreciate your reply but, i am talking about situations when all is set for go untill you actually takeoff and the system fails to work. the category i fly is actually allowed to depart with AFX with deviation in dispatch procedures

[1jz]

multis81, still waiting for the email..

[aerobat77]

i m just looking for material that is approved by the relevant authority and allows the crew to manually feather before reaching the acceleration altitude in case auto fx fails.

sweet discussion gents, but in the very rare event that a turboprop gets in real life at hot and high conditions with max takeoff mass an engine failure exactly at rotation AND autofeather fails simultany you are pretty close to crash before you have time to think what and why happened.

its not the question of the authority, its the question of emergency procedures for the type and common sense of the crew. all single engine operation procedures and performance numbers are regarded to a feathered prop -so the answer should be obvious what to do when decision is made to survive such a scenario.

without any doubt one memory item should be to change underwear after landing , i quess you will not find this in the checklist . :ok:

[1jz]

Aerobat77 thanks for ure input

Lolz I m sure u always carry extra underwears.. I think I should keep a few in my crew bag too.

U are right it's about crew cognitive thinking, common sense and prompt action. Actually if a pilot does something out of the checklist n SOP then I am sure it's not considered 100% legal. So, best would be to take proactive actions n devise ideas n procedures so that even an average pilot can get out of the situation n one doesn't have to be an ACE to change his undies.

Still waiting for some1 to throw in some material.