Use of trim on circuits- necessary?

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Nanolight
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Use of trim on circuits- necessary?

Post by Nanolight » Sat May 27, 2006 12:22 am

This was a point of contention in my last hour's flying (I haven't had many, so please don't launch in here telling us all how great you are. This is a learining excersise, remember?).

Anyway, I reckon you don't need trim when circuit training.. it's just another thing to be thinking about, right? When you have enough going on? It's more suited to cross country flying when you need to be able to relax a bit and not be holding pressure on the stick. My instructor reckons that the trim is a tool to help you maintain a precice airspeed (essential for landing) and is extremely important for flying circuits, and that every time you make a pitch adjustment (or put out flaps etc) it needs to be adjusted, and this is especially true for circuits.

Why can't you just leave it in the neutral position, and deal with forward pressure on approach, and the reverse on climbout? What are your thoughts?


*By the way, the guy feels very strongly about this, to the extent that we nearly fell out over it.
Smoke me a kipper, I'll be back for breakfast.

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michael747
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Post by michael747 » Sat May 27, 2006 4:41 am

Hey Nano :D ,

The trim is there to make it easier :shock: on youself as a pilot,
You dont have to use it if you dont wanna,
but if your practising circuts for an hour or so you'll fell it after- it really is just to make life easier.

I can see your point that its one more thing you have to remember but at the end of the day it is ONLY one thing :) !!!
It takes a whole 2 or 3 seconds to trim the plane in my plane (Grob G115A) so i cant complain.

Eg: I could take off, trim, and let go of the contols and the plane is really stable, almost as if its on auto pilot.
After i retract the flaps then it takes another 2 secs to trim and then let go of the controls- Life's easier with trim!!!

Happy campin!

Is it really hard to trim your plane?? What do you Fly????

Mickey D :D

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Post by shrtfld » Sat May 27, 2006 9:01 am

Hi Nano

I have to agree with Mickey D and your instructor. Once you use the trim properly you will not regard it as something extra. It does become instinctive. I fly a PA28 where the trim control is on the ceiling. You just adjust automatically without even looking at the trim tab control. Its all part of the skill set that makes you a better pilot.

Trim has additional advantages when properly set. It is possible to take hands off control column for short periods (or longer subject to air conditions) to do paper work or change frequencies. If you are flying S&L and need to do something such as look at charts you'll find the weight of your hand will pull or push the control column without you even realising it. Trim does help counter that because you'll feel the inadvertent movement of the control.

The guys who design aircraft include trim to make life easier for you. Why ignore its existance?

Happy flying.
Shrtfld

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Post by ceatach » Sat May 27, 2006 9:36 am

The one advantage (I can think of) in doing nanolight's neutral-trim circuits is that during a touch-and-go, the trim is set for the take-off and doesn't need to be adjusted. When using trim, on final the nose will usually be trimmed high and so when full throttle is applied, the aeroplane will tend to pitch up early and sometimes causes the pilot to either re-trim during the takeoff :shock: or pitch down.
However, I think keeping the aeroplane trimmed is important for the safety of the flight as well as the comfort of the pilot.

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Post by Lambada Crazy » Sat May 27, 2006 10:10 am

In the Warrior II i have noticed when on final the nose trim is mostly down, then when you are applying full power on the Touch and Go, the controls feel like they are almost locked to the Panel!.
When a flight is proceeding incredibly well, something was forgotten.

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Post by Terry Murphy » Sat May 27, 2006 11:36 am

Hi Nano,

Contrary to popular belief, the elevator trim is not just a muscle tension relaxer .
It?s nothing more than a happy logical consequence of its intrinsic function that it relieves fore/aft stick forces.

The primary effect and purpose of elevator trim is airspeed control.
I?d bet serious money that that?s the message you are getting from your instructor

Of more immediate concern is the fact that you would seek a second opinion to that of your instructor and the thousands of flight training manuals that keep beating out the same persistent mantra
? TRIM for Airspeed ?
Power, Attitude, TRIM ? Attitude, Power, TRIM. etc etc.

As the guys have pointed out here, using the trim will allow you free up some ?hard disk? capacity and allow you to absorb the next phase in your training that the instructor has lined up for you.
As ?shrtfld? has said, use of the trim will eventually become instinctive with practice.

I?m no expert by any stretch, but I would question the wisdom of wrangling with your instructor on such a fundamental aspect of flight.
If he or she thinks you have a tendency to make up your own rules on the basics, it will do absolutely nothing for your upward progress.

If your instructor says ?TRIM? Then TRIM till your hands are raw and then TRIM some more for good luck

Regards,
TM
Last edited by Terry Murphy on Sat May 27, 2006 11:40 am, edited 1 time in total.

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OW wright
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Post by OW wright » Sat May 27, 2006 11:39 am

michael747 wrote:Hey Nano :D ,

The trim is there to make it easier :shock: on youself as a pilot,
You dont have to use it if you dont wanna,
but if your practising circuts for an hour or so you'll fell it after- it really is just to make life easier.

Life's easier with trim!!!


i agree, especially on finals, you you want to have the aircraft trimed for landing makes it a hell of a lot easier, then you only have to make small adjustments on approach.
also get the hang of using the trim now as your going to need it when your doing simulated insrument flying, which can be very tiring and your only going to make it worse if you don't learn to trim the aircraft now.
trim is not not just for the cruise ,but also for climing and decending.

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Nanolight
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Post by Nanolight » Sat May 27, 2006 7:28 pm

Thanks all! Some useful stuff there...

Thanks Terry in particular.... I am not "arguing with" or "going against" my instructor per se. I do however, think that things of this nature should be discussed (for hours on end if necessary), until the student is happy, and the instructor is happy that the message has been gotten accross.

I have flown with 2 other instrutors. The first was pretty lax about the trim and let me do my thang, so to speak. The second (an extremely accomplished pilot) just left it neutral and didn't bother with it.

Ara he's just pissed off cause he told me to re trim on short final and I told him that he was too obsessed with the trim for his own good and that in my opinion it was over rated, and basically I didn't follow his instructions. I won't be doing that again though. If he says fly, I'll say how high? :P

I don't want to get on his bad side. I reckon he has The Anger.
Smoke me a kipper, I'll be back for breakfast.

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Post by AndyMax » Sat May 27, 2006 8:20 pm

listen to your instructor.

ALWAYS TRIM.

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Post by tom in weston » Sat May 27, 2006 8:53 pm

I was allways instructed to "trim as required" if you have a force in the control column why not trim it out, this includes the circuit. if the plane is properly trimed in the downwind for example, performing your pre-landing checks are a little more relaxed and you are less likely to forget something.

Also on finals if you trim for your approach speed lets say 70kts this concentration demanding finish to a flight is alot less stressful.

the best part i think of trimming on finals and you must remember as you reduce speed you must re-trim, if you get into the habit of trimming and are properly trimmed all the way down finals the flare and hold off are alot easier, especially in a crosswind - LISTEN TO YOUR INSTRUCTOR.

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Post by Terry Murphy » Sat May 27, 2006 9:40 pm

Hi Nano,

I see the drift of your original question a bit more clearly now.

Years ago, when sheep were afraid and Rallye?s didn?t rust.
There was a certain (ahemmm!) lady instructor that used to whack the ?stick? into the legs of any student that didn?t comply with her precise directions.

The stick would hit high enough to give a whole new meaning to ?keeping the ball in the centre? :oops:
I was always amazed how a few stripes of the?lash? improved my hearing and concentration levels.

Of course, as time went on I found out that she was a really good instructor? but I remember promising myself that if she ever did hit the target I would peg her through the canopy and be the first student in history to take off dual and land solo.

Good luck with your flying,
TM

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Nanolight
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Post by Nanolight » Sat May 27, 2006 11:29 pm

Thanks!

I think the moral of the story is LISTEN TO YOUR INSTRUCTOR!

Even if he does have The Anger...
Smoke me a kipper, I'll be back for breakfast.

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Post by Yahweh » Sun May 28, 2006 11:17 am

If you want a good workout on your biceps don't bother with trim. Saves me a trip to the gym :D .

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Post by alphaLaura » Sun May 28, 2006 3:09 pm

Also on finals if you trim for your approach speed lets say 70kts this concentration demanding finish to a flight is alot less stressful.

Exactly. Why make it harder for yourself to keep that perfect approach attitude on finals? I know that when I was first figuring out how to use trim to give my arms a break, I was seriously questioning its usefulness. It does become second nature though; as soon as you re-set the power your hand should go to re-trim and so on. Flying out of trim is a pain in the neck. Or arms.
The hardest thing about flying is knowing when to say no.
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Post by shamrock/heavy » Mon May 29, 2006 2:53 pm

Nanolight i can see how you think that there is a lot to do already without having to think about trim also.However as you go on in flying you can instinctively sence a pitching force and you will trim it out without any thought at all, at least that is the way it is for me. There are situations where i decide not to trim, they are:the first 500ft after take off and when flying a circuit or arrival in gusty conditions.My reason for doing this is because in both situations i always have one hand firmly on the controll column and the other firmly on the throttle awaiting the unexpected, put simply trim is not a priority for me at those times.listen to your instructor thats what your paying him for and keep trying you will get the hang of it shortly.

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