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Trimming the Rudder during a V1 Cut

  • Thread starter Thread starter FD109
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FD109
Thats about about right new guy no experience and he's rewriting the AOM. In 24 yrs at my company including 9 in the sim maybe 1 in 20 don't use trim. And thats glass and steam.:cool:
 
Nice thread.

Boy a fella has to be careful with you guys when you start digging into the books. Do you know how much dusting I had to do to get into the old 9 manuals. I hadn't really realized how long ago that was. I checked some other old books too (707 series, CV880, L-188, SF-340) and my current bird. Couldn't find anything specific that mentions when to trim or when not too. Basically I tend to agree with enigma and the UPS gentleman.

[Note to Chicago: Whoa! Forget tying to trim while the airplane is on the ground or anywhere close to it. That's a big no-no in my book and not required in anything I've ever flown. In some airplanes the difference between V1 and Vr can be as much as 20 knots. It would be a real bad airplane (and never certificated) if you had to trim to keep it going during that interval. In your Saab V1 and Vr are virtually the same. You don't need to trim to "keep it on the runway" because its not on the runway anyhow. Just fly the thing and don't do anything else until you get to that magic 400 AAE (except confirm the auto corsen). (I guessed where you are due to your Avtar .... tell Scott I said don't do that ... and never mind who I am. If Dan was your systems instructor, are you sure he really told you that?).

I've taught in both the 9 and 70 series as well as a few other transports, both jets and props, along the way. We never taught anyone to trim before the climb was established and it was pretty much "do nothing but fly" until out of 400 AAE. By that time the gear is in the wells and you definitely know which one(s) aren't running. I see nothing wrong with rudder trim at that point and would even recommend it.

The profiles generally change at the 400 ft point in the props vs jets scenario because the props can't usually accelerate to flap retract speeds while continuing to climb. You have to level, accelerate, clean up and then climb again. All the jets can continue the climb while accelerating. Some birds need aileron input (usually the props) more than others and in my experience about 1/2 rudder throw is usually enough (except in those 2-out same side scenarios that few get to wrestle with nowadays).

In the present airplane, company procedure calls for engaging the autopilot at 600 AAE, but the clean up and checklist doesn't start until 1000 AAE. As you can guess, there will be some rudder trim before the AP is selected on (but it is not mentioned specifically in the books).

It's hard to judge where the trimming that caused the dispute actually occured in the example you gave us. If it took place before the aircraft was under control, on heading and climbing nicely, I'd lean towards the FAA dude, but if it happened when those things were already done, then I think its a matter of "technique" and subject to pilot preference.

Some of the Federales are great people, but there are also (unfortunately) quite a few that moved over from the GA segment with "attitudes" and little experience in the real world. As long as they don't get too carried away we can live with it until they learn. What really gets me going is an "expert" with a few hours in a sim and a new rating who just has to give us the benefit of the FAA's wisdom.

PS> FD109 - looks like we were both writing about the same time and I was just too slow. Exactly what I suspected. Times never really change.
 
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filejw said:
FD109
Thats about about right new guy no experience and he's rewriting the AOM. In 24 yrs at my company including 9 in the sim maybe 1 in 20 don't use trim. And thats glass and steam.:cool:

Filejw,

In 24 years at EAL and 11 since then at other less "prestigious" places, I saw just about the same ratio of trimming early versus later.

I initially give students the option on when to trim; however, if they are having problems with V1 cuts in the sim I demonstrate the technique of trimming immediately. It makes an absolutely perfect V1 cut virtually effortless and usually makes believers out of them.

In 14 years of instructing and being a check airman I have always taught that technique, and I have never had one of my students bust either a type ride or a PC. Yeah, I know I'm bragging, but I AM proud of that!
 
Re: More on the fed's concerns

FD109 said:
I just got some more details on the fed's concern about trimming the rudder early in the V1 cut profile (see my first post in this thread if you haven't), and some of the details are really surprising. Second, he was there purely as a "gee whiz" observer. <<< >>> He is a brand new fed who apparently comes from a general aviation background.

You know the worst part is that its not really surprising at all. It's happening more and more. That kind of stuff used to be a rarity back when we had GADO and ACDO, but ever since they made it FSDO you see more and more of it. You don't get to many air carrier types applying for those jobs.

Third, the new fed was also concerned that the company's procedure is for hands to come off the throttles at V1. (Just like every other operator that I know of.)

When I saw that it made me laugh. You're headed for trouble buddy. <G> I had one of those yokels tell me I be in serious difficulty if didn't stop calling those things throttles and start calling them thrust levers and, if that wasn't enough, call for Max Power one more time (instead of max thrust) and you're out of the ball game. No, I'm not making it up.

Fourth, the fed was not typed in the DC-9 and was at the training center to get typed before serving as an inspector on the airplane.

Not unusual at all. Most of them have no line experience nowadays. General Aviation or retired military desk pilots. We actually got a #1 Fed once who had never flown a jet. Matter of fact he never flew anything bigger than some light twin. They crammed typed him and he was scared to death of the airplane. Had us bumping up ref speeds and causing all kinds of problems. Wouldn't let us taxi on one, and so on. It took two years to straighten him out. I think the Company got so tired of burning up brakes that somebody finally got the nerve to discretely tell him to cool it or they would refuse him. Now he acts normal, we never see him unless he needs to sign something.

At first I used to worry and b1tch about those types and argue with them all the time, but now I just ignore them. Sooner or later they give up and go away.

One time the company had to let a guy go because he couldn't upgrade to a different type. Low and behold, about 8 months later he turn up at the local FSDO as a Fed. Times change my friend.
 
In the E120 at ASA, we still do flight training in the airplane. Part of that training are V1 cuts. The rudder in that situation will be almost on the floor. Generally, the way I do it and have seen instructors teach it is to get control of the a/c, get it flying and the gear up, then trim it up at least some. If you don't, your leg will be quivering pretty quickly and compromise the control that you do have.

In the sim, we also simulate loss of rudder boost and extreme prop overspeeds (140% + Np.) With the loss of rudder boost, it is all you can do to press the rudder to the floor. Trim is critical and needs to be applied pretty soon after getting the a/c under control. With the prop over speed (which this a/c is famous for-hope I never see it!) both the ailerons and rudder are on the stops. Here too it is pretty important to roll in trim soon.

The a/c will be controllable in both situations without trim, but having trim in soon will enable you to relax a little and better deal with the problem.
 
In the Dorkjet, if you don't have that rudder trimmed (or close to it) by the time you hit 160kts, you're going to be in a world of hurt (this is in the sim, mind you. I have heard that a failure in the plane isn't quite as dramatic).

The dornier has a rudder tab that is engaged below 160kts to make it easy to push on the rudder. Above 160kts, the servo-tab is locked out and it takes a LOT more pressure to move the rudder (to prevent you from snapping it off at those mind-blowing cruise speeds we acheive).

My personal preference... stomp on it.. on the (very short) climb to acceleration altitude, trim that bad-boy out.
 
Another one of my pet peeves

Man-oh-man I hope the Fed in the original question looses this argument.

It really irritates me when people can't differentiate between *technique* and *procedure*.

An incorrectly performed procedure deserves to be called out but give me a break...if someone has a different technique and no parameters are busted then who cares?

By the way, I was trained in the Metro to get things settled down and then *ask the NFP* to roll in the appropriate trim (all the aileron trim and 'one swipe' of rudder trim worked nicely).

Personally I always waited until acceleration altitude and completed all memory items before I even thought about trim but I'd never bug somebody about their use of trim if the airplane was still under control.

Fly safe
 
Fly the Airplane

Fly the airplane, climb out, clean up and when you get it all corralled feed in the trim. I have never seen anyone around here do anything different. My personal cue on remembering the rudder trim is when I feel my leg start to burn about 5 minutes after the V1 cut. :)
 
Here is even a better tip, at least for the busdrivers: Start feeding in trim as soon you get airborne (takes about 7 seconds to get the right amount of trim in on the -330), then slap an a/p on, this makes life a lot easier after you have lost a donk.
 
Hmmm..... deiterly must be from Oz.

IN Australian slang (and perhaps other places) an engine is a "donkey" or "donk"
 
It's true! We really do learn something new every day.

I lived over there for two years, and never heard that term. Probably just didn't make it to rural Queensland. Of course, what they called a "roo" in Sidney, we still called "one of those big hairy things with the big feet and thick tail that hops really fast."
 
Not from Aus. First time I heard "lost a donk" was back in -94 with Mesa. I guess you learn something everyday, thanks.
 

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