The perfect landing, Practing slow flight.

The perfect landing, Practing slow flight.
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The perfect landing, Practing slow flight. - 3/28/2008 3:07:53 PM

Sempiterna

Posts: 40
Joined: 3/28/2008
From: Denver, CO, USA
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So I got a bug in my crawl a few weeks ago and I wanted to see how perfect I could bring in my landings. I fly full scale Cessna 172/182s.

So I thought, lets transfer some of that knowledge to my rc flying. How can I fly very slowly and stay in the air, keep from stalling and maintain my stability.

So I took out my trusty Avistar 40 and i said, lets fly slow. Trimmed full up elevator. Slowed the engine down to about 25% power, and let the speed bleed off, adjusted my throttle until i was flying in a very nose high attitude, with about 40% power, and i was maintaining altitude.

I decided to fly around, doing some shallow turns and test my controls. Sluggish, as I'd expect in the real thing, big altitude drops in the more than 5% bank turns.

Back to the flight school.. adding power in turns to maintain altitude. After a few flights I was able to fly around, with full up trim and keep the plane controllable..

now, for landing practice. I went up, entered slow flight with my avistar, and brough it around to downwind, then base, then on final, reduced power and realized the plane was too far out, i was coming in too low for my descent rate. so, i put in some power, maintaining slow flight, flew around the patern and came back in, this time closer. I noticed that my rate of decent was pretty high, so I added about 2 clicks of power and my descent rate shallowed, but I still had that classic nose high attitude. I flew this all the way down to the runway and just as expected, ground effect caught the plane and its higher than normal descent leveled off, so, as I watched the speed bleed off I kept thinking about my flight instructor for full scale, flare.. flare.. so I slowly pulled the elevator back more and more and i watched the nose come higher, and the plane touched down on its 2 main wheels, the nose stayed off the runway for about 2 feet, then came down and the plane rolled to a very quick stop, my entire landing distance from touchdown to full stop was a matter of 4 feet.

After practicing this, i've been able to master landing on a paper plate, stopping within 3 feet of my touchdown point.

Every landing is soft and I have people watching saying, wow.. how do you do that?!

Has anyone else ever really experimented with flying rc like this? Whats your experiences and how did it work out for you?

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Hangar 9 .40 Cub - 40 Sized Hangar 9 Twist w/Saito .72
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Post #: 1

RE: The perfect landing, Practing slow flight. - 3/28/2008 3:30:11 PM

dick Hanson

Posts: 10069
Joined: 12/12/2001
From: slc, UT, USA
Status: online

This method is seldom practiced by newbies -
Of course it is the preferred method
Most "flying lessons" consists of following the model and not crashing
assuming a proper slow flying attitude is just plain ol scary to many new and a lot of old flyers
it's full bore or glide in - VERY common.
Many "trainer" are simply tooo heavy
Others setup all wrong and againtypically the throws are setup as objective points ( the operator applies full up or full down to do changes in attitude)
I STLL get guys asking how much throw to put on a typical model
My own setups are simply, as much throw as practical and then the tx is set to make things smooth around center . NOT dull - smooth.
Even full scale stuf like the afore mentioned full scale have more throw available than typically used .

< Message edited by dick Hanson -- 3/28/2008 4:11:41 PM >

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RE: The perfect landing, Practing slow flight. - 3/28/2008 4:10:12 PM

Sempiterna

Posts: 40
Joined: 3/28/2008
From: Denver, CO, USA
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So, it is practiced by the more advanced, better pilots then?

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Post #: 3

RE: The perfect landing, Practing slow flight. - 3/28/2008 4:12:24 PM

dick Hanson

Posts: 10069
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From: slc, UT, USA
Status: online

quote:

ORIGINAL: Sempiterna

So, it is practiced by the more advanced, better pilots then?

NO it is taught by a GOOD instructor from day one. Many so called instructors havelimited experience -example I often see the guywho has just accomplished his first landing - attempt to instruct
this is common. after all it is a hobby.
For this method to work - the model has to be very very forgiving as response time and implimentation of learned reflex -in landing needs a confidence and understanding of what transpires on a landing

other than "I made it".
My own first rc landings were ONLY good because I had a lot of practice in landing control line competition stunt models .
These are "flown " to the deck.

< Message edited by dick Hanson -- 3/28/2008 4:17:32 PM >

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Post #: 4

RE: The perfect landing, Practing slow flight. - 3/28/2008 4:20:09 PM

Sempiterna

Posts: 40
Joined: 3/28/2008
From: Denver, CO, USA
Status: offline

Ahhhhh.. yes, that would make sense to do that. I learned it by accident more or less, just trying to improve myself.

What tips would you have for me in furthering this and trying to perfect it even further?

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World Models Skyraider Mach 2 w/ OS .40LA - Spektrum DX7

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Post #: 5

RE: The perfect landing, Practing slow flight. - 3/28/2008 4:28:09 PM

gboulton

Posts: 1862
Joined: 5/28/2005
From: La Vergne, TN, USA
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Sempiterna,

What you've done is...on your own 9and kudos to you)...started to learn something that, imo, should be taught to EVERY pilot (scale AND RC) from day one:

The stick on the right of the transmitter (or yoke/stick in a full scale bird) is a FAST SLOW control, NOT an up/down control.

quote:

Back to the flight school.. adding power in turns to maintain altitude. After a few flights I was able to fly around, with full up trim and keep the plane controllable..

Yep. Works the same way in cruise flight, on approach, or in any other phase of flight too. That stick on the left is NOT a fast/slow lever...IT is the up/down control.

quote:

I noticed that my rate of decent was pretty high, so I added about 2 clicks of power and my descent rate shallowed, but I still had that classic nose high attitude.

Go figure.

===============

Please understand...I'm not making light of your efforts. Far from it, I think you are to be praised for taking the time to apply your full scale lessons to your RC planes. (IME, the reverse can work too...don't be afraid to at least explore some of your RC lessons in the full scale airplane)

I am, indeed, concurring with dick Hanson here. I think the practice and lesson(s) you've posted about should ABSOLUTELY be taught by ANY qualified instructor...in EITHER environment.

Take a look at NTSB reports, or listen to RC folks out at the field, and you'll find that a TREMENDOUS number of crashes involve, at some point, a stall and/or spin (the latter being unable to happen without the former). One must wonder...how many of these incidents would simply have failed to occur if our "instinct", when the plane started descending faster than we wished, was to PUSH FORWARD rather than PULL BACK. If only our INSTINCT was to treat the elevator as a fast-slow lever, we would IMMEDIATELY know that what we want in that situation is NOT a higher AoA, but MORE AIRSPEED...and our reaction would be to drop the nose. Then, if we were too low, understanding that throttle=altitude, we would...as YOU did on landing...ADD POWER.

Kudos to you again. Spread the word. This single lesson would, imo, save thousands of model airplanes every season...and probably a few lives too.

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Post #: 6

RE: The perfect landing, Practing slow flight. - 3/28/2008 4:28:11 PM

crasherboy

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From: Bryant Pond, ME, USA
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I to have a full scale licence ,but I won't be getting a medical again. I have around 150 hrs in Cesnas and a few other planes ,and I was taught all of this. Slow landings,takeoffs from a soft or short field,etc. A Cesna 152 can stay flying at 40 mph,assuming no bad gusts of wind ,and believe me if you have an emergency landing and the spot you pick out is not to friendly,slow is better as long as it don't slip out on you[stall]. So,I don't see why one could not apply the same to model flying. I have an RCM Funster ,and this baby will fly SLOW and stay in the air,with full flaps. But you need to practice,practice and practice.

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RE: The perfect landing, Practing slow flight. - 3/28/2008 4:29:58 PM

gboulton

Posts: 1862
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From: La Vergne, TN, USA
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quote:

ORIGINAL: Sempiterna
What tips would you have for me in furthering this and trying to perfect it even further?

I know you were asking dick Hanson, but hopefully I can jump in here.

Stick and Rudder: An Explanation of the Art of Flying

Enjoy

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Post #: 8

RE: The perfect landing, Practing slow flight. - 3/28/2008 4:40:13 PM

gboulton

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From: La Vergne, TN, USA
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quote:

ORIGINAL: crasherboy
So,I don't see why one could not apply the same to model flying.

(slight tangent here, but still topical, I think)

One absolutely can...and, imo, should...BOTH ways.

It's always baffled me (and I don't mean you, crasherboy) how many don't get that very concept. What works in a scale plane works in RC, and vice versa.

Ok, no flame wars here...yes, I know, there are many significant differences between the two.

But, fundamentally, they're airplanes. They do what airplanes do for the reasons airplanes do them.

Raise a wing's AoA beyond the point where it deflects air downwards, and guess what...stall. Really doesn't matter if we're talking about a .25 sized trainer or a C-130...you pass the critical AoA, and that airplane will stop flying.

Turn an airplane, and its weight goes up, thank you G-Loading. Again...don't care if it's a 50cc QQ Yak, or a DA-20 Katana. G-Loading increases the weight the wings must support. End of story.

And on and on and on.

SO many things I've learned, or shown a knack for, or had trouble learning, or whatever have seen a relationship between full scale flight and RC flight. Time and time again, I hear people say "You can't apply so and so to the other side, because..." and yet, fundamentally, you almost can't NOT apply the lessons of one to the other. Sempiterna's post is living proof. I'm sure EVERY ONE OF US who flies scale birds heard, and now practices, the idea that during an approach, use throttle to maintain altitude, and elevator to maintain speed. And what do you know...it worked on his RC plane too! How about that? And airplane acted like an airplane. Who'da thunk?

I know...we'll possibly have dozens of posts explaining why real airplanes can't do what our models can, or how our models don't respond the same way real ones do, or whatever. And sure...there are a great many differences in CAPABILITIES between the two.

But...again, fundamentally...they all aact the same. They do what airplanes do for the reasons airplanes do them, and the basics of flying, and flying well, are the same for both.

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The free man will ask neither what his country can do for him nor what he can do for his country. - Milton Friedman

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Post #: 9

RE: The perfect landing, Practing slow flight. - 3/28/2008 7:49:52 PM

Sempiterna

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From: Denver, CO, USA
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aye, the realization that the rc models are more maneuverable to me only shows that the RC planes can do exactly what the scale counterparts can do, and more

I dont think I'd try some of these 3D maneuvers in a scale plane

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RE: The perfect landing, Practing slow flight. - 3/29/2008 12:53:34 AM

Jim Thomerson

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From: Austin, TX, USA
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Many years ago I was testing a freeflight model at a local airport. Some one in a Cessna was shooting touch and goes. Later a couple of cropdusters came in. They came in perpendicular to the runway. under the electric lines, made a stall turn onto the runway and taxied maybe 20 feet into the hanger. I was impressed.

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RE: The perfect landing, Practing slow flight. - 3/29/2008 2:52:08 AM

Steve Steinbring

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Joined: 7/17/2007
From: Homestead, FL, USA
Status: online

Interesting thread!

Alot depends upon the aircraft one is flying be it full scale or model. I flew in the military where we used powered approaches and landings. Otherwise depending upon the aircrafts weight and/or its design it would probably stall. Usually approach speeds were somewhere around 1.3 above charted stall speed for a given weight, with threshold speeds around 1.1 above computed stall.

Realize any airplane can be stalled at any attitude at any airspeed if L/D max for that flight regime is exceeded. I've been stalled out at over 500kts heading straight for the ground in a high G maneuver; the only way to start flying again was to let off the G's to decrease wing loading.

There are considerable differences between flying high lift light aircraft, vs. heavy weight transport aircraft and high speed fighter designs the stall characteristics vary.

Learning the flight envelope and characteristics of the aircraft you are flying is good airmanship!

< Message edited by Steve Steinbring -- 3/29/2008 2:59:27 AM >

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RE: The perfect landing, Practing slow flight. - 3/29/2008 5:02:11 AM

BMatthews

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From: Burnaby, BC, CANADA
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I once had a rather clean Quickie 500 I flew with a .25 on it as a sport model. The ONLY way I could land it without pushing it into the ground was to lay up into a nose high slow flight setting. If I tried to slide it down in the all so common shallow dive it would "flare" and fly the entire length of the runway and off the other end with pretty much zero altitude loss.

This sort of nose high draggy approach doesn't need to be at the stall speed as Steve points out immediately above. However for some of us it will SEEM like we're right on the verge of a stall and disaster. Learn the skill and how to read the model the proverbial 3 mistakes high and soon you'll be descending with a lot more control and predictability on the contact point.

Lots of great info from all in this thread even though it's more about flying practices than aerodynamics.

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