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wanfahmi
20th Mar 2011, 15:27
Hi,
I have a question on QRH procedures. I'm new on the ATR72.

Extract of QRH
----
Page 0.01
Procedures Initiation
No action will be taken (apart from depressing MC/MW pushbutton):

until flight path is stabilized.
under 400 ft above runway, except propeller feathering after engine failure during approach at reduced power if go around is considered

----
Page 1.04
ENG FLAME OUT AT TAKE OFF

UPTRIM.............CHECK
AUTOFEATHER...CHECK

If no UPTRIM
PL 1+2.....ADVANCE TO RAMP

BLEEDS and PACKS FAULT lights....CHECK LIT

Above 400ft AGL
PL affected side.....FI
CL affected side....FTR THEN FUEL SO
BLEED engine alive.... OFF if necessary

----END QUOTE

My question:
If there is no Auto Feather, should you feather the engine below 400 feet AGL?
My brains says no, but others say MUST.

Any help is appreciated.

Chazbird
20th Mar 2011, 16:10
If there's no auto feather and you want to meet any of the climb segments you'll have to feather the propeller manually. In fact, depending on conditions there's a real good chance it won't climb at all, after. The ATR-72-500 climbs at 400 ft a minute single engine at gross weight on a ISA standard day.

This is from another carriers FCOM, not ATR's:

....
PF: auto feather check
PM: no auto feather
PF: Manual feathering right/left (or 1/2) CL's reduce memory items.
PM: points to PL
PF: confirmed
PM: moves PL to 48 degrees PLA
PM: points to right/left (or 1/2) CL
PF: confirmed
PM: moves CL to feather/fuel cut-off.
...

Ringi
20th Mar 2011, 16:14
It's not recommended to manually feather below 400feet. However the aircraft will struggle to climb single engine without prop feathered even with successful uptrim. Manual feather may be necessary below 400feet. Obviously AFTER confirming correct condition lever with colleague

wanfahmi
20th Mar 2011, 16:29
I understand of the struggle to climb. I tried it in the simulator.

Almost all turboprop pilots that I spoke to comments are the same, ATR struggles to climb if the dead engine is not feathered.

Why would the manufacturer produce such a QRH? Would this struggle to climb be factored in the performance charts?

quazz
20th Mar 2011, 16:53
By the time you've correctly identified the problem and started the memory items, you are usually above 400ft before you get to the condition levers.

skysign
20th Mar 2011, 18:20
Quazz : If you are empty yes, Heavy & Hot with old engine ( 120/124 PW ) not a chance you will be at 400ft if autofeather has not function. ( I do not know about the 72/500 never flown it ).

The no action below 400' agl come from ATR & ATR assumed that uptrim & autofeather will always function.... therefore not doing anything until 400 feet will prevent rushing and shutting down the wrong engine. And for years that what my company procedure was, no action below 400 ft.

Until a couple years ago people questions that procedure ( including the FAA ), all the climb performance, obstacle clearance, acceleration altitude are calculated with uptrim & autofeather working ( Unless MEL and specific weight restriction will apply ).
So if uptrim &/or autofeather does not function it is critical to act in order to meet the climb performance and being at a safe altitude specially at airport with obstacle surrounding it( mountain, building, antenna,...).

There is a specific action, who is often overlooked, to prevent shutting down the wrong engine and give you one last chance to not f... up in the stressful moment.

The QRH said : IF no Autofeather
- Affected PL ----- reduce to 48 degree angle( 48 to reduce drag below that you will be in the Beta Range )
- Affected CL ----FTR THEN Fuel Shut Off

THEN : is the most important word in that check list. As a flying pilot never call FTR then Fuel Shut OFF in one sentence.
First call FTR and leave it there and check you are still climbing and look around that everything is normal, and THEN when you are sure that you are climbing out call for Fuel Shut Off. By doing that you will save your day because if you have call for the wrong engine you still have a chance to bring back the CL to max rpm and the PL to the ramp.
Once you go to Fuel Shut Off It is over, at 400 feet there is no way you have time to restart that engine.
It may seemed obvious but I have seen so many time in the Sim, people just spit out the call out and the Non Flying pilot going from FTR to Fuel Shut Off in nearly one motion. ( TAKE YOUR TIME )

Good luck in your training, ATR even being under power ( in my opinion ) is still a fun airplane to fly.

Skysign.

Chazbird
20th Mar 2011, 18:48
Come to think of it while it may have happened, I don't remember any sim session where a V1 cut occurred and the auto-feather didn't work. It would, however, be useful to demonstrate. I've done them in the airplane, but it was very light and there really isn't a power setting that did or could replicate 0 thrust and a unfeathered propeller. I've seen in the MEL takeoff without auto-feather and the weight/temp limitations are extreme, so obviously it is for ferry flight and no passengers/freight.

If you have to manually feather below 400 ft, it'll be busy, and by the time you are half-way through that you will be at or near 400ft and it'll become rather more busy with the accelerate/clean-up items.

I also agree about waiting after moving to feather before fuel cut-off.

The ATR, in my opinion, in many circumstances, can be a very high-workload airplane.

wanfahmi
20th Mar 2011, 19:22
Thank you for the replies.

The 48 Degrees PL is not in my QRH (dated 2009?/2010?)
(29 Degrees to simulate feathered engine on 72)

I've tried not feathering the engine with engine cut at V1. Struggled just to reach 400ft (ISA +15, Max TO weight, Sea level) but it did climb.
Full rudder with bank on live engine just to keep it straight.

The practical side of it is understood.

What's buggering me is this part:
No action will be taken (apart from depressing MC/MW pushbutton):
-until flight path is stabilized.
-under 400 ft above runway, except propeller feathering after engine failure during approach at reduced power if go around is considered

If there is no uptrim on the live engine, the memory item calls to push the power up.
But is silent on feathering the dead engine until ABOVE 400ft.

Chazbird
20th Mar 2011, 20:44
It appears the assumption is that the auto-feather will always work. If you don't experience a no auto-feather engine flame-out on takeoff scenario and you're curious maybe you can ask them to fly one as an extra. In the real world the system might be 99.999999% reliable, but one never knows.

The last place I worked testing the ATR AF was done on the taxi in on the last flight of the day, presumably avoiding maintenance from running it up, and if you guessed correctly, handing an airplane over with a fault to maintenance not at the start of the days flights. In that situation you could fly with a in-op AF system all day and not know it. Others probably do it differently, one hopes.

aviatorhi
21st Mar 2011, 00:01
Fly the airplane with guidance from the book, don't use the book to fly the airplane, it has gotten people killed. If auto anything stops working (or doesn't work) you wouldn't say "there's no procedure for this" and give up, would you?

Also if you want to justify your actions on paper:


No action will be taken (apart from depressing MC/MW pushbutton):
-until flight path is stabilized.

Excellent, as soon as you stabilize the aircraft you're free to do what you need to do to keep it airborne. Full (or near full) control deflection is not a fantastic way in which to fly the airplane, not only is the prop causing drag but on some airplanes you've got spoilers coming up as part of the flight controls. You're putting a LOT of drag on the airplane when you're trying to climb, you can take all that drag away by feathering the engine, so why on earth wouldn't you?

BrasiliaCaptain
21st Mar 2011, 00:04
I concur that if you experience an engine failure below 400' AGL and the ATPCS does not feather the inoperative engine, 'you' (meaning the flight crew using company procedures and good CRM practice) should feather it ASAP. This was a part of our FAA-approved training program and was worded as such in our company's immediate action items for such an occurrence.

It was not uncommon for us to have procedures that went into considerably more detail than ATR's. These were all FAA-approved.

If you want to get an idea of the impact of a failed and unfeathered engine, look up the performance penalty in terms of weight with the ATPCS/autofeather system deferred.

skysign
21st Mar 2011, 02:59
Wanfahmi :

What's buggering me is this part:
No action will be taken (apart from depressing MC/MW pushbutton):
-until flight path is stabilized.
-under 400 ft above runway, except propeller feathering after engine failure during approach at reduced power if go around is considered

If there is no uptrim on the live engine, the memory item calls to push the power up.
But is silent on feathering the dead engine until ABOVE 400ft.

On approach if you lose an engine you will never have uptrim and in function of your config ( PWR Mgt position ) and PL Angle & Torque you might or might not get autofeather. therefore if you go around you will need to feather engine manually in order to obtain the appropriate climb performance.

Reducing PL 48 degree : I see only 2 possible explanation why is it not in your QRH.
Each QRH is taylor to each operator, and maybe ( I really doubt it but who knows ) your company calculate your climb performance, Acceleration altitude with propeller unfeather and therefore they do not want the crew to manually feather to avoid any mistake.
Or they just forgot to put it in the QRH and you should question them about it.
In order for the ATR to be certified by the FAA the A/C has to meet certain criteria for climb performance and unless you have uptrim & autofeather you will not meet those performance.( it is part of the certification process )

Escape Path
21st Mar 2011, 04:11
Operating in environments where ISA+15 or ISA+20 and high elevation airports are the norm, I recently asked one of my instructors "how much does engine-out performance is reduced when the prop is not feathered?" He said in a very straight forward way: "Long story short, you will realise your life is sitting on the auto-feather".

While practising engine failure in flight he proceeded to prove his statement. He reduced one engine to idle, we proceeded with the immediate action items, and as soon as we feathered the propeller it felt like the airplane immediately cut loose from a rope that was holding it back. If it felt like that already in cruise configuration, at altitude, levelled and at cruise speed one better feather that thing :sad:

Our standard briefing states the following:
"Failures at or above V1:
- Failures other than engine failure: No corrective actions below 400ft
- Engine failure: (...) Confirm auto-feather operation. If auto-feather failed, execute manual feathering as follows:
PF "protects" live engine; PM feathers the propeller on the failed engine at PF's command"

1jz
6th Aug 2012, 20:56
Dear all members, the document references you provided seem very helpful to what I require. Can sone one please get me the stated docs for reference. I would appreciate.
Thanks

N sorry for digging up an old thread