The rule of thumb in larger airplanes is to stop trimming once you have the flaps all the way out and are on your final approach speed, don't trim to land. Not that it doesn't work but you are pre-planning a go around. As some of you have already said in a higher horsepower airplane you are going to just about do aerobatics if you have trimmed nose up then have that proverbial cow on the runway just as you go through 10 feet. Go arounds do happen below 50 feet. If you think it takes some muscle to land a 185 without trimming you should try any older transport airplane that was built before hydraulic systems came into being.

Matt
With the Robertson that I had on a 206, when it was windy never did land with full flaps! I kept all the other pilots but 1 out of it as it flew completely different than a standard wing. If I remember right, had to keep some power on and fly it right to the ground. Different aircraft altogether!
Fact is the guy who flew 1 of the other 206's flew it off the end of a strip that he normally flew out of, he just flew thru the willows for about a hundred feet or so before he got any elevation. thats what the Sportsman cuff is for!! covers up all those willow marks!!?? My fault as the one he flew was getting a 100 so had him fly the Roberson, My mistake!!!! Sure impressed the 5 guys that were on board???? Takes awhile to get all the green of the prop to!
Porterjet, I agree, Would not be a skinny pair of pilots that were keeping the nose down on a DC3 or an 18
GT

Yes, GT I think that is why I am throwing out some thoughts on this as I haven't figured out the consistent sweet spot for the Robertson in all wind conditions and variations on the load. Agree that the Sportsman is probably better on wheels with big tires so you get the deck angle, but hoping the Robertson works out for me on floats and skis where you start dragging your tails before getting the benefit of the Sportsman? Yes, I have had to do the go arounds on sand softer and rocks bigger than they looked on a low pass. Snowmobiler pulled out on me last year, but that was a takeoff. Elk on landing with no go around, but had enough runway to add power and hop over to land beyond.

So no contention on the force required to fight the go around power with full flaps and full aft trim and agree that it is an excellent thing to be aware of. Given that, I still have a couple questions. Whether 'tis nobler in the mind to suffer an occasional tricep strain from the outrageous fortune of a cow on the field, Or to build biceps against a sea of troubled daily landings. That is the question. So is it better to trim for the rare incident or reduce the control forces for the daily landings - assuming that you are able to control the aircraft on a go-around with the stated parameters?...

The other question I posed before is with regard to the best performance with a trimmable stab. When sailing, if you have your sails set to grab as much wind as possible but then have to keep yarding on the rudder to maintain course you are going slower than if you trim the sails so you don't create the rudder drag. Obviously not comparing apples to apples, but the question is then: If I put in full forward/nose down trim on the stabilizer and then fly the plane with increased elevator forces, will it stall at the same speeds? May have to go out and check.
Thanks again, Matt

Whole other thread, but improper trim setting on take-off will surprise you too.

My T-Cart on Edos tried to bite me hard one hot day. I was heading out north of Lake Berryessa stuffed with camping gear, gas, and floats full of ice and beer. I musta used up a mile of water to get the damn thing up on the step, and when it finally did... It was "POP" nose straight up, and me waking up real fast from my hangover and pushing as I found myself wallowing in a departure stall about 20 feet above the water. Luckily there was nothing to run in to.

All it was, was the trim set for the last landing, and I missed it in my flow before I cobbed the throttle and that mighty O-200 roared to life. Of course the beers had nothing to do with it.

Gump

Matt 7GCBC wrote: Whether 'tis nobler in the mind to suffer an occasional tricep strain from the outrageous fortune of a cow on the field, Or to built biceps against a sea of troubled daily landings. That is the question.

MTV is spot on (as always). Always decide whether you are going to do a 2 or 3 point landing, preferably before you turn final, and then stick with it. Most of the really atrocious landings that I've seen students do (not me, of course. ) if not due to just being behind the plane were attributed to changing their mind in the flare.

Always, always, always keep the airplane tracking and pointing down the runway. Don't sacrifice directional control for that perfectly smooth landing. Sometimes a firm landing is better than a greaser anyway.

If in doubt, go around. If that 2 pointer gets a little slow and turns into a 3 pointer and then goes BONK and your landing starts looking like a takeoff, it's always ok, and sometimes necessary to go to "radar power" and take it around and try it again. When you get a little more experience you'll be able, with a long enough runway, to add a little power and get stabilized again and make another landing on the remaining runway. I don't remember any pilots who have made a "balked landing", but I can name plenty who should have.

Have fun and happy landings!

Oregon180 wrote:

Matt 7GCBC wrote: Whether 'tis nobler in the mind to suffer an occasional tricep strain from the outrageous fortune of a cow on the field, Or to built biceps against a sea of troubled daily landings. That is the question.

Genius. Haha!

http://www.backcountrypilot.org/gallery ... pos=-11915

Made it to the dirt today....headed to our circut in the am with lowrider.

Sure wish I could learn how to post pics better...

Matt
Go find some ugly old geezer that as a lot of Robertson time in the back country, I was kind of the impression that you were referring to short ugly narrow strip where your choices are limited. I think all the other places you might as well trim it to fly on the ground and land. Then it won't matter who you have riding shotgun!!
There are definitely many different ways to get these things on the ground!!! Some work for me some work for you!!
Now whether we are working on triceps or biceps that is a question for each pilot to reach way down in there heart and come to terms with there inner being, and the to see if you can get the darm airplane to agree.
You have got the Robertson, find out what it likes and then fly the heck out of it. It is a different bird with the way they do things.
As always, have as much fun as you can stand or get away with and keep smilin
GT

M6RV6 wrote:Now whether we are working on triceps or biceps that is a question for each pilot to reach way down in there heart and come to terms with there inner being, and the to see if you can get the darm airplane to agree.

GT

Fail to overcome trim forces on landing: reach down and give the trim wheel a few turns, and land.

Fail to overcome trim forces on balked landing and go round: maybe crash and die.

I'll give my biceps the workout

This is a great thread.
This whole trim thing got me to wondering, so yesterday I go up to altitude and pulled 40 flaps and trim all the way aft, flared at 60, waited a few seconds and firewalled the throttle.
my god it is a lot of throws on that wheel to get it trimmed.

Now I'm wondering how much worse it would be with a full load?

GumpAir wrote:Whole other thread, but improper trim setting on take-off will surprise you too.

My T-Cart on Edos tried to bite me hard one hot day. I was heading out north of Lake Berryessa stuffed with camping gear, gas, and floats full of ice and beer. I musta used up a mile of water to get the damn thing up on the step, and when it finally did... It was "POP" nose straight up, and me waking up real fast from my hangover and pushing as I found myself wallowing in a departure stall about 20 feet above the water. Luckily there was nothing to run in to.

All it was, was the trim set for the last landing, and I missed it in my flow before I cobbed the throttle and that mighty O-200 roared to life. Of course the beers had nothing to do with it.

Gump

I have electric pitch trim on my S-7S, and I once took off with full UP trim after resting my flight guide on the top of the stick, right on the UP button. On takeoff my first thought was that I had somehow snagged my garden hose and it and the 20 lb. traveling sprinkler were hanging from the tail! Then I noticed the trim indicator light saying different....man that is some powerfull trim! I try and make it part of my pre flight routine to check it, but I already have so many items to check before flight (ENGINE RUNNING, PARKING BRAKE OFF) that I hate to add one more thing

Small Tail Caddy wrote:This is a great thread.
This whole trim thing got me to wondering, so yesterday I go up to altitude and pulled 40 flaps and trim all the way aft, flared at 60, waited a few seconds and firewalled the throttle.
my god it is a lot of throws on that wheel to get it trimmed.

Now I'm wondering how much worse it would be with a full load?

A friend of mine with a 108-220 and full aft trim took off on a cold day and said it really got his attention! Thought he was going to break the seat back getting it pointed back to earth. I'm sure from the ground it looks rather impressive (so I'm... err, he was told ).

I trim about 1/3 aft and found that to be the "sweet spot" in my Stinson.

Just a thought here, and I know there are many considerations, but I would think that for most, most of the time, when you decide to do the last minute go 'round, and cobb the throttle, probably after a second or two, you could pull the throttle back some, relieve pull on the yoke,roll the trim wheel foward some, dump some flaps, then adjust as needed. ????????

Yes, you CAN do all those things, assuming you've been properly trained, and you're not distracted by whatever caused you to go around in the first place. Yeah, right....

The point is, you don't have to put yourself in that situation in the first place. If you are going to do a wheel landing, rolling in a little nose down trim prior to touchdown will help in two ways:

1) At the touch, just relax the backpressure you've been carrying, and the plane will stick...now push forward, and you're well into a good wheel landing. It's a piece of cake--give it a try--it HELPS on the touch. I suggest that what we REALLY want to do at the touchdown is to relax. If you're holding a LITTLE backpressure just prior to the touch, when you touch, relax for a half second, which allows the plane to stick, then move the yoke forward to keep it there. It's very natural.

2) IF you do have to execute a go around, the trim is already in a position where it won't require Charles Atlas to overcome the trimmed condition compounded with power. This is a characteristic of Cessnas with trimmable stabilizers.

Now, as to the Robertson kit: Look out the window as you deploy flaps. Watch the ailerons. As you deploy 10 degrees of flap, the ailerons deploy as well. At 20 flaps, the ailerons deploy (droop) further. As you add 30 flap, the ailerons reach their maximum deflection. Now, apply full flaps (40), and watch the ailerons. They actually RETRACT some with application of full flaps. So, if you want to minimize AILERON deflection, DON'T use 30 flaps. Actually, 20 and 40 flaps have very close to the same aileron deflection.

And, if your ailerons DON'T do as I just described, get a mechanic to FIX the system. I have seen two Robertson equipped airplanes where the ailerons continue to droop further with application of full flaps. That is NOT airworthy.

Learn the machine and it's characteristics. I've flown Robertson airplanes several thousand hours, and I love the kit. You need to learn it's characteristics, though, and learn to work it. Once you do, you won't want to go back.

One advantage of the Sportsman cuff on a Robertson airplane is that the Sportsman includes aileron gap seals, and aileron gap seals almost eliminate all the aileron effectiveness issues that the Robertson airplanes' pilots sometimes whine about.

MTV

Mike Thanks for the explanation, some of us can think it but not put it down.
Another thing that I think some people don't understand on these things is that when you get real slow, you lose the aileron effectiveness.
That where you remember that you have feet!! when you go up and do a stall at altitude you really should be using your rudder not the ailerons??
Same thing when you get close to the ground and trying to get it to stall just as your tires touch.
The rudder will lift the wings when the ailerons won't, Had to learn that when I started flying the Maule.
Thanks for listening
Be safe Have fun
GT

mtv wrote:..........One advantage of the Sportsman cuff on a Robertson airplane is that the Sportsman includes aileron gap seals, and aileron gap seals almost eliminate all the aileron effectiveness issues that the Robertson airplanes' pilots sometimes whine about. MTV

Sounds like maybe VG's would also help in the aileron effectiveness area. BTW nice crack about R-STOL pilots whining- ya kinda snuck that one in under the radar.

I have not flown a Robertson airplane with VG's. They MIGHT help with that, but I pretty much hate the VGs on my 170, for several reasons, and I'd never put them on a Cessna wing unless I was really convinced that they were going to do something really good for flight characteristics. They do really good things on a Cub, but not on my airplane.

Now, the hot ticket might be to find someone who offers aileron gap seals for Cessnas, and just stick a set on a RSTOL airplane.

I hear a LOT of pilots complaining about the roll control of the RSTOL airplanes, and in fact, this kit does degrade the aileron effectiveness of the airplane some. On the other hand, the kit REALLY improves the STOL performance of the airplane. Much of the complaining about the roll control could/should be dealt with by good training in the RSTOL airplane, AND by application of good judgement.

I have slept in the airplane once or twice in narrow sloughs with a BIG crosswind and trees creating rotors, because I wasn't bright enough to realize prior to landing that I couldn't take off out of there safely with the RSTOL airplane on floats.

But, that's true of ANY airplane. It is possible to get yourself into a situation where the airplane is limiting, and while that may be inconvenient, it need not be unsafe--assuming the application of good judgement.

If I were running a RSTOL airplane these days, I'd try to find an aileron gap seal kit, and install that first and see what it does for me. I'd bet that will improve aileron effectiveness greatly all by itself.

But, in the meantime, understanding HOW the RSTOL kit works, when to use full flaps, vs half vs 3/4 flaps and what the limits of the airplane are will go a long ways to making the airplane work for you.

Remember, while the RSTOL airplane does have slightly degraded crosswind capability, on the other hand, it significantly improves STOL capability. For example, the C-185 stall speed goes from 51 knots to 37 knots with installation of the RSTOL kit. ANd, those are documented, flight tested and demonstrated numbers, produced in a full FAA flight test program. The RSTOL also provides a comprehensive AFM Supplement, with full takeoff and landing performance tables. Try and find that kind of data and honest stall speed numbers for ANY other "STOL kit".

MTV

As usual I find myself odd man out... 99.9% of the time I can find no good reason to fly an airplane out of trim. The mechanical part of my mind says give the airplane what it wants to 'feel right'. 'Forcing' anything mechanical never amounts to much good. A typical approach for me is trimmed to two fingers on the yoke, and a hand on the throttle. Power pretty much controls the whole she bang. While I have not tried it, I would bet that in this configuration you could probably land a 180 - 185 with ONE hand (the throttle one)... There are a few instances in which I purposely 'mis trim' an airplane, but simple everyday landings are not one of them, regardless of the flavor of the landing.

The second odd man out part is this: again in keeping with the 'not forcing mechanical things' train of thought, how often do you really honestly 'cobb' the throttle? I am not contesting the need for as much as full throttle in a go around, I am questioning the rate of, and thought process behind that application. Think about it this way, in the decent I just described, the airplane is 'almost' flying the whole way through the decent. A simple blip of the throttle and the wing is alive again. So once again, I give the airplane what it needs to fly, then adjust that flight as necessary to climb out and try again, forcing a go around is probably just as bad as forcing a landing... Speaking of 'bigger' horse power planes, try 'cobbing' the throttle on a really high hp vs. weight airplane, and pitch will be the least of your worries, as you torque roll to your way to your maker....less hp = faster/more cobbing to get what you want, more hp = less cobbing/rate, no rocket science here...

RSTOL? it is mechanical too... force the ailerons to do what you want, and sooner or later they will disappoint you, as others pointed out, learn to use the RSTOL like it was intended, and it will never let you down.I find it fascinating that guys complain about turning RSTOL airplanes.
Heres a couple interesting RSTOL tid bits:
MAF (an undeniable group of experts in the bush) has RSTOL on all of their piston Cessnas...
Larger AirTractors (an airplane which undeniably makes more turns per hour than the average Joe) has what amounts to RSTOL in their flap/aileron configuration...
Flying into Jeffco friday night reported winds winds were high, to say the least. As a result of a nasty Wx induced sinker, I found myself on very short final, needing every bit of hp I could muster, and wishing for a tad more, just to arrest the decent and not land on the 'running rabbits'. Full flaps, full throttle, and yes RSTOL... No 'Mr.Toads' wild ride, no exotic pitch up, nothing harrowing... but what did catch my attention was how much left turn was induced... Still, no big deal, decent arrested, 'cub short' landing, business as usual. Different strokes for different folks

Take care, Rob

Rob wrote:As usual I find myself odd man out... 99.9% of the time I can find no good reason to fly an airplane out of trim. A typical approach for me is trimmed to two fingers on the yoke, and a hand on the throttle. Power pretty much controls the whole she bang.

AMEN!!!!!!!!!!!!!!!!!!!!!!!!!!

Gump