ATR42 - Pitch/Power Couple?

[ATR Newby]

Can anyone please tell me how the pitch/power couple is arranged on the ATR42?

I am curious due to it's high-wing & high-mounted engine design:-

Which way does it pitch when power is applied & conversely, when power is reduced?

Is it the same as, or the opposite to, a low-mounted engine design such as your typical Boeing?

Thanks...

[Jagbag]

Hi ATR Newby

The power - pitch changes are pretty standard; reduce torque -nose down and vice versa. Though the nose up tendency is comparatively less when u increase torque.

Just be careful about the yaw with ATPCS fail with one engine failure- shes a b**** to keep straight but u can manage with a touch of aileron.

Started flying as yet - if you don't mind me asking?

Hope this helps.

[ATR Newby]

Hi Jagbag,

Many thanks for your reply :ok:

I was hoping that would be the case - kind of thought that it would be an airworthiness requirement, but needed to check.

No, haven't started flying yet - just trying to get some answers to some (dumb) questions to get ahead of the game!

Thanks for the tip regarding the ATPCS - not too familiar with this, but will watch out for it.

Whilst writing, can I ask if this aircraft has an autothrottle system, or any sort of IAS HOLD facility?

Thanks again...

[Jagbag]

No auto throttle--- but you can set a speed control during climb and descent. The normal SOP is to keep IAS during climb ( in turbulent conditions keep basic pitch mode) and ROD during descent.

If you set IAS in level mode then the aircraft will climb and descend to maintain speed if the torque is increased or reduced.

Hope this helps.

[ATR Newby]

Jagbag: Understood - most helpful :ok:

Thanks a lot!

[click]

Just watch out for the ice accretion...has a tendency to become a snowball in icing and handles like a little piggie:}

If you want to be a little more nervous in icing conditions, read up on "Unheeded Warning" the inside story of American Eagle 4184 by Stephen Frederick.

Other than that it's a great airplane for visual slam dunks:E

Good luck

[ATR Newby]

click: Thanks for the advice & your good wishes :ok:

Regarding that book - it's okay, I'm nervous enough already :D

[White Knight]

Click - what drivel you utter!!!!
The wing leading edge de-icing boots have been completely redesigned since the American Eagle 72 went down. I have flown both the ATR 42's and 72's in heavy icing - not planned but it happens - and if you operate with a modicum of common sense, airmanship and in conjunction with the FCOM's you'll have NO PROBLEMS.
Don't listen to the scaremongers ATRboy - it's a fun aeroplane to fly..

[click]

You've got a right to your wrong opinion.

Redesigned yes, but I smell politics here and it ain't gonna be my voice on the CVR. I prefer the NTSB version and wholeheartedly agree with you that if the current procedures in the FCOM are followed, then there SHOULD be no problems....all I said was that icing in this thing should not be underestimated.

[White Knight]

Nothing political at all. Icing or the possibilities of it need to be respected in ANY type.
Consider the tail stall due to icing - happened to more than one jetstream in the past. So no, icing is not just a problem with the ATR.
Also bear in mind that the ATR that crahed in Illinois was HOLDING with flap 15 in FREEZING RAIN and DRIZZLE - never a good thing to be doing. And I believe the skipper was not in his seat when the first control problems became apparent, leaving it all down to a fairly inexperienced FO to deal with.

[Miserlou]

I'm with White Knight on this. Click, you're talking nonsense.

You contradict yourself when you say,
Quote.
"that if the current procedures in the FCOM are followed, then there SHOULD be no problems."

Is there any aircraft of which the same isn't true?

The ATR has probably been tested more in icing conditions than any other aircraft in it's class.

Politics? Yes. There's nothing the American aircraft industry would have liked more than to have banned this 'foreign' aircraft from operating in the US.

[Danish Pilot]

Yep, the ATR was indeed tested in severe iceing by the NTSB. The same test was offered to Fokker, BAe Aerospace, Bombardier and some other. I cant say they said no, but fact is none, other than the ATR, went through that test. Wonder why..!? :yuk:

The old rule "leave and avoid iceing condition" is still valid.

[No_Speed_Restriction]

Sorry, I'm still campaigning for Basic Mode in the Climb as opposed to IAS.Call it personal preference. :ok:

[HugMonster]

click, the ATR involved in the Roselawn accident was holding in severe icing conditions with flaps extended and the A/P engaged.

I have looked on the internet for a full copy of the CVR transcript, but most versions start just before the accident. I have, in the past, seen a full transcript and it makes horrifying reading.

Put simply, the crew operating in a totally unprofessional manner.

During the hold, the captain spent something like 35 minutes down the back chatting up the cabin crew. Even when on the flight deck, he was still chatting them up, appartently paying little attention to the aircraft. There have been allegations that he was having an affair with one of them, but I have no information on that.

During the hold, there were (from memory) five incidents of the pitch trim whooler going off. This should have alerted even the most inexperienced pilot to the fact that the A/P was having severe trouble maintaining the aircraft in the manner commanded. Yet not a peep out of the crew.

The ATR was quite unjustifiably slammed by the NTSB and various authorities after that incident. Even though it was demonstrated quite categorically that the crew acted in a manner opposed to the instructions of the FCOM, the ATR was victimised, even though ATR themselves ordered modifications to the boots, and paid for some very extensive tests.

I have flown both 42 and 72 versions and find it a very nice aircraft indeed. I had no problem whatsoever with icing, through two European winters, and flying in Alpine conditions.

Like any aircraft, if you don't follow the FCOM, it will bite you in the bum.

PS NoSpeed - that's a very bad habit.

[No_Speed_Restriction]

Didnt say I do it I would just prefer to avoid the "magic carpet ride":p

[wandrinabout]

No speed - I hear ya and agree

Huggie - disagree
Why would it be a bad habit if it produces a better result and avoids the roller coaster?
Just a matter of being aware of what situation you have put yourself into and monitoring accordingly.
However, in icing/level 2 on, it may well be more prudent to use IAS mode, particularly at the higher end of the weight scale where there is less margin between red bug and climb speed.

Have you ever sat down the back of a 72 when some goon up front has been climbing in IAS mode while the crew are pushing carts up and down the aisle??

[Danish Pilot]

Agree! If you fly it in basic pitch (4 or 5 degrees) it gives a much smoother ride. The idea of keeping it in ias mode, and then assume everything is fine, would in my oppinion be just as much "bad habbit" as flying in basic pitch and not watch your intruments.

If in iceing, sure, ias mode!!

[ZFT]

ATR Newboy

There is a superb video from ATR showing the icing tests conducted at Edwards AF base during 15-19 December 1994 and 5-6th March 1995.

It’s well worth watching, as it should dispel any doubts about the ATR