Elevator trimming technique
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In fairness to IO540, I think we knew what he meant. There are very few high or low G manoeuvres in PPL training, and use of the trim wheel is not encouraged during them.
But in fairness to FIs, (and taking on board the 1G assumption), all the FIs I ever ecountered taught: know your speeds, select the speed with attitude and power, then trim to maintain that speed.
But in fairness to FIs, (and taking on board the 1G assumption), all the FIs I ever ecountered taught: know your speeds, select the speed with attitude and power, then trim to maintain that speed.
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Why don't light aircraft have AoA indicators?
LIFT RESERVE INDICATOR
I've flown with one of these, and they work very well. Requires set up, but well worth it. It does not work well on very slow aircraft, as there is inadequate total air pressure to operate it at very slow speeds (which is when you need it most!)
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Yes, of course, the elevator trim controls the IAS in level flight, because for a given aircraft configuration it controls the pitch attitude and that relates to the IAS.
If you go into a spiral dive then your IAS will increase
The reason why appreciating that the trim controls the speed is so useful is because most normal flight is done with the wings level, or nearly so.
I think the space shuttle did that, and similarly with most re-entry vehicles before it, to lose speed once in the uppermost layers of the atmosphere (because once you drop below the escape velocity then re-entry is guaranteed, which is highly desirable) though obviously not rolling through 360 degrees
That's why one does S-turns on final. That is arguably a lot safer than sideslipping, which on some aircraft types might cause problems with elevator airflow.
If you go into a spiral dive then your IAS will increase
The reason why appreciating that the trim controls the speed is so useful is because most normal flight is done with the wings level, or nearly so.
one way to slow down without changing altitude is to pull to higher angle of attack and roll 360 degrees.
That's why one does S-turns on final. That is arguably a lot safer than sideslipping, which on some aircraft types might cause problems with elevator airflow.
In practice experience pilots fly often fly the aircraft with the elevator in cruise flight in calm air. They know how much to tweak the trim to correct very minor altitude excursions just as they start to develop, or wind in just the right amount so the aircraft settles right on the glideslope.
However with respect to ab intio instruction it is important that students do not try to fly the airplane with trim as the inevitable result is they start chasing the airspeed and altitude with the nose nodding up and down and the aircraft never stabilized. Instead good instructors concentrate getting students to concentrate on recognizing and holding the correct attitude and then trimming the forces off so that the aircraft will fly hands off. Proper trimming is an important skill that should be practiced because if the aircraft is not in trim the aircraft will deviate away from the attitude you have set when you look away.
However with respect to ab intio instruction it is important that students do not try to fly the airplane with trim as the inevitable result is they start chasing the airspeed and altitude with the nose nodding up and down and the aircraft never stabilized. Instead good instructors concentrate getting students to concentrate on recognizing and holding the correct attitude and then trimming the forces off so that the aircraft will fly hands off. Proper trimming is an important skill that should be practiced because if the aircraft is not in trim the aircraft will deviate away from the attitude you have set when you look away.
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I think the space shuttle reverses in upside down for a few minutes against whatever thrust it's got left from onboard fuel and then pushes through to the right way up for re-entry. Not like there is any air up there to generate resistance.
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Yes; it does that initially to drop out of orbit, but it also flies S-turns when there is some air about.
It was during those S-turns that one of them (the one with the damaged tiles) broke up. So, probably not wise doing S-turns in a PA38
It was during those S-turns that one of them (the one with the damaged tiles) broke up. So, probably not wise doing S-turns in a PA38
probably not wise doing S-turns in a PA38
Fwiw, I retrim frequently - the pitch control in my plane (182RG) is very heavy and it is tiring to be even ever so slightly out of trim. With my newish autopilot (STEC30), if I want to use it in climb or descent, I have to trim for rate of climb (or descent). It can be done but it takes a VERY fine touch. The tiniest possible movement of the wheel makes a noticeable difference to attitude and hence speed (both vertical and horizontal).
But in the Pitts, I touch the trim only when entering the pattern, to trim for final speed. Oh, and when it goes to full nose down all by itself, to yank it back to the right place, which it invariably does after a tailslide.
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It's not wise doing ANYTHING in a PA38
And it is more than safe doing S turns in a PA38 and also sideslipping them.
Although I will admit that stupid spring tension setting abortion of a trimming system on the PA38 is utter pants.
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Oh, yeah, I guess it's been a while since the naturally recurring "slag the Tomahawk" theme crept into a thread again!
Is it time to take up sides again?
Is it time to take up sides again?
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Aye opening lines are
C150/152's are smelly heaps of poo that don't do anything to teach the students how to fly properly. Apart from yours of course which is the only none smelly one in excistance.
And tommys are dangerous heaps that will kill you by spinning in if you get anywhere near (within 20knts) the published approach speeds. O aye the tail shakes and wobbles like a fat burds arse doing the 100m hurdles when you stall it or spin it.
C150/152's are smelly heaps of poo that don't do anything to teach the students how to fly properly. Apart from yours of course which is the only none smelly one in excistance.
And tommys are dangerous heaps that will kill you by spinning in if you get anywhere near (within 20knts) the published approach speeds. O aye the tail shakes and wobbles like a fat burds arse doing the 100m hurdles when you stall it or spin it.
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Or you can take my view that these are all aircraft designed to go from A to B with minimum interference from the pilot and non of them are really meant for enjoyment of flying them, for this there are far better aircraft, but at the end of the day they will all get you into the air and I would rather be flying any of these than sitting on the ground instead.
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It's not wise doing ANYTHING in a PA38, and least of all trying to fly the thing. Maybe sitting it in it parked on the ramp, watching the planes on the runway, with a good book and a glass of something, would be OK, though a deckchair would do the job better.
- you will get your feet wet as the water rises on the cockpit floor (due to perished door seals). Eventually new forms of intelligent life, optimised for flying NDB holds, will evolve in that Primordial soup.
- the plane will get heavier and heavier and eventually the landing gear will collapse, as the fuel tanks fill up with water (due to perished filler cap seals). Water is 1.38x heavier than avgas and that will be enough to collapse the landing gear.
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Well as I have seen rubber marks on the underside of the wing due to a landing in a PA38 I suspect your theory won't happen with the gear collapsing.
The primorial soup which is poo hot at NDB holds though is a possibilty depending what glue they have stuck the carpet down with.
The primorial soup which is poo hot at NDB holds though is a possibilty depending what glue they have stuck the carpet down with.
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Yes, of course, the elevator trim controls the IAS in level flight, because for a given aircraft configuration it controls the pitch attitude and that relates to the IAS.
Originally Posted by 5296s
It's not wise doing ANYTHING in a PA38, and least of all trying to fly the thing.
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BPF he is an auld hamble **** who is lost in the dark ages when it comes to instucting. That is if they arn't a walt
http://www.pprune.org/flying-instruc...irst-solo.html
The verdict on that one in mind is assured. He isn't what he posts.
http://www.pprune.org/flying-instruc...irst-solo.html
The verdict on that one in mind is assured. He isn't what he posts.
Last edited by mad_jock; 19th Nov 2011 at 07:51.
Mad Jock
I see what you mean
I see what you mean
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BPF he is an auld hamble **** who is lost in the dark ages when it comes to instucting. That is if they arn't a walt
