Forth Maneuver, Inverted Flight

Well, the first few have drawn some great input, don't stop now.

Once again, what we're looking for is your description of flying the maneuver. Walking and talking us through it. Simply giving pointers as to how we should do it is helpful, but a full description of technique and reasoning is better.

Judges please make your comments on the errors you see most and causes as well

Inverted flight might not seem like a "maneuver" but it is judged and scored so we need to do it right.

After the inside loops I use the first interim lap to descend to level flight altitude and the second to feel out the wind. I have a tendancy to climb into the wind and descend on the downwind half of the lap so I try to determine what corrections I'll need to watch for in the 3rd & 4th laps. I've found with my higher powered models the ascent and descent problems aren't as pronounced, but still there. Actually I'm sure they are there in upright flight as well but inverted flight seems to amplify the effect even if only psychologically. The 3rd and 4th laps ARE the maneuver. As I fly them I try to anticipate the corrections I'll need as I transition from upwind to downwind sides on the circle. I don't do it very well, but I seem to be making progress. After the judged laps are complete I try to maintain good interim laps to set up for the outside loops, I don't relax much and try to make them flow into the outsides.

Don't want to turn this into a vertical vs palm up discussion please, but just for the record I fly with the handle vertical.

I don't remember noticing the climbing and diving tendencies. Could these be because your airplane is noseheavy?

The thing I don't understand is why some guys hold their handle in a horizontal position.. They don't do this when flying upright. It seems to me to be a bad habit. I have heard why they do it, but don't buy it. Seems to make one more potential problem.
The hard part of inverted flight for me is trying to stay ahead of the plane. It is easy to let it lead you. So I turn more to my right as I enter into inverted flight to try and stay ahead of it. Also, it never fails, my first two laps are always better than 3 & 4! Go figure. I think my problem is I'm trying to do the outside loops (in my mind)before I get to them. Have to concentrate on the maneuver at hand.

"The thing I don't understand is why some guys hold their handle in a horizontal position.. They don't do this when flying upright. It seems to me to be a bad habit. I have heard why they do it, but don't buy it..."

I began learning inverted flight this season, and what I found out is that my hand just "naturally" went horizontal when the plane was inverted. It wasn't anything I thought about, until I discovered it (much to my dismay), and then I set about "unlearning" it. I discovered that I had even been doing it on lazy-8's. Since I hadn't spent much time doing either maneuver, there wasn't much of a habit to overcome, and I'm happy to say I'm now a vertical-handle person when inverted. My inverted laps are still kind of shaky, but so far I haven't gone the wrong way at the wrong time...

Alright Randy, I will bite on this one, but I will be describing the incorrect way that I am currently flying this one.

At the end of the third inside loop I fly another half loop at the same size as the first 3 and in the same location. While this portion of the flight is not judged, I think that it looks nicer which gives the entire flight an overall better appearance. Usually the airplane is near my flying altitude at the first lap. This point is always directly downwind so it easy to remember. I use lap number two to verify my altitude using the judges shoulders and anyone that might be standing around. Note that I said that I fly this incorrectly as I usually let my wrist rotate and face up while I am flying. Actually I did not think that this was a bad deal for flying as I could control the altitude by letting the airplane fly slightly ahead of me to gain a little altitude and I could lead the airplane a little to drop some. I too have some small altitude problems in the wind (rising in the wind and dropping with the wind at the tail) so I would just lead or fall behind a little as required to maintain the same altitude. I try to maintain the same level for all the laps after lap one again for appearances. The transition into the outsides generally starts at the end of the sixth lap with me stopping and starting to add a little down control to start the loop.

Since the clinic, I have been trying to maintain the vertical hand position and have found that I can fly this way. It takes a great deal of concentration, but I am able to fly a fairly decent set of level laps. Will continue to practice this until it becomes as natural as the old method.

Last Fall, I was flying fairly often, and had corrected my tendency to tilt the handle about 20 degrees counter-clockwise from vertical. It seemed to be easy enough to do, and also seemed to me to make an improvement on my inverted. This Spring, it was back, so I got to try to break the habit again. I think the lesson was learned, to keep after thos bad habits or expect them to return.

I can't recall crashing a model while just flying inverted laps, since my first try to learn, with a new Ringmaster, circa 1961. Later, I learned to fly inverted with a combat model, probably doing around 100mph, and didn't crash. This past November, I found myself sneaking a peek at my flight time on the stopwatch, while flying inverted. That, I consider to be a bad thing, and I am not concentrating on the task at hand. Better the ground crew do the timing as needed for tank adjustment.

Regarding actual contest inverted laps, recall the earlier discussion about the definition of level flight. IF the ground is not level, do not fly at constant height off the ground. Think of flying on a pond, standing in the middle, and flying level to the "waterline". This would be a good thing to bring up at the Pilot's Meeting. In fact, if the site is not pretty close to dead flat, the ED should put this on his list of topics to discuss, and be sure the Judges are paying attention.

From the Judges point of view, one of the issues is keeping track of the level laps flown after the inside loops, while writing down the score for the loops. Sounds easy, but late in the day, after chasing around the circle for changing wind directions, and after having some drunk lunatic pounding on your motel room door at 1am, it can get to be a problem. The issue, of course, is to judge the correct laps. For some fliers, one lap is just like another, but those guys are rare.

Observing the pilots, I have noticed that some can concentrate from the start signal to the time the wheels stop rolling. Others "take a break" while flying level laps, and it shows. If you can learn to concentrate for the full 8 minutes, it should help your whole pattern. Steve

I wasn't drunk. Besides, it wasn't I.

>Well, the first few have drawn some great input, don't stop
>now.
>
>Once again, what we're looking for is your description of
>flying the maneuver. Walking and talking us through it.
>Simply giving pointers as to how we should do it is helpful,
>but a full description of technique and reasoning is better.
>
>Judges please make your comments on the errors you see most
>and causes as well
>
>Inverted flight might not seem like a "maneuver" but it is
>judged and scored so we need to do it right.
>
>After the inside loops I use the first interim lap to
>descend to level flight altitude and the second to feel out
>the wind. I have a tendancy to climb into the wind and
>descend on the downwind half of the lap so I try to
>determine what corrections I'll need to watch for in the 3rd
>& 4th laps. I've found with my higher powered models the
>ascent and descent problems aren't as pronounced, but still
>there. Actually I'm sure they are there in upright flight as
>well but inverted flight seems to amplify the effect even if
>only psychologically. The 3rd and 4th laps ARE the
>maneuver. As I fly them I try to anticipate the corrections
>I'll need as I transition from upwind to downwind sides on
>the circle. I don't do it very well, but I seem to be making
>progress. After the judged laps are complete I try to
>maintain good interim laps to set up for the outside loops,
>I don't relax much and try to make them flow into the
>outsides.
>
>Don't want to turn this into a vertical vs palm up
>discussion please, but just for the record I fly with the
>handle vertical.
>
>Randy Ryan
>AMA 8500
>SAM 36
>I fly 'em all and love it!

Randy,

This is an excellent observation. The two "free" laps between the inside loops and the judged inverted laps shouldn't be wasted. Most flying sites present particular problems in stable inverted flight due to obstacles, judges and spectators position relative to the wind, and other factors. There will often be parts of the circle that will repeatedly effect the flight path of the airplane as a result. Use those first two laps to find out where and what happens and be prepared to deal with it during the two "counters".

In addition, your goal should be "zero" deviation from the elevation at which the ship enters the judged laps. Don't let yourself be intellectually nudged to accept anything between four and six feet as "perfect". The judges will be extremely critical of this maneuver (if they aren't, there'll be a lot of 40s...ever seen a "lot" of 40s?) and any deviation will result in a greater deduction of points than will a single deviation in a complex maneuver like the square eight. Be meticulous. Remember, in AMA scoring there are just as many points to lose on a simple maneuver like inverted as there are in a complex one. Don't give 'em away.

By the way, a matter of style here. I don't like to take a whole lap to establish inverted flight level. Not only because of the desirablity of two full laps to explore the nature of our airspace, but because of style which influences the judges.

There is a tendency to treat the laps between maneuvers casually because they "don't count" on the score sheet. Don't fool yourself. The entire pattern from the time you enter the circle until the wheels stop turning on landing is a subjective show for the judges. I'm certain that 99% of the guys and gals who are willing to spend a day or more judging do their utmost to be as objective as possible; in the final analysis, however, there is no way to eliminate impression effects.

For this reason, you should, once you've got the maneuveers themselves pretty much under control, start to think of flying the entire flight as a choreographed entity with no wasted motion, no "free" laps, no breathing spaces. Every control input should be a part of your presentation to the judges and, even if not a judged part of the flight, should look like it was done intentionally and with precision control.

Thus, in this thread, we should be looking at a consistency in the manner in which we leave one maneuver...the inside loops in this case...and the next...inverted. The rule book used to say (and I'm embarrassed to state because I'm too lazy to check, might still do so) that level flight after each maneuver is reached one quarter lap after completion of the previous maneuver.

No big deal, I suppose, since the book also states where each maneuver starts and stops for scoring purposes. But, a precise controlled return to level flight (or preparation for the next maneuver) following each maneuver just looks professional and "impresses" the judges whether they realize it or not. It shows that you are in control from start signal 'til carrying the airplane off the circle. It looks cool and it looks in control...which is what precision is all about.

Bottom line, finish your inside loops and make a smooth controlled descent to inverted flight level within a half lap or so of the exit from those loops...and from each successive maneuver. This is the PHD stage of Inverted 101!

Great info Ted.
I would only add that a common mistake made by judges is judging laps 2 and 3 or laps 4 and 5. I always try to fly all of the inverted laps as if they were all being judged. Don't take a chance that the Judge, no matter how experienced will judge laps 3 and 4 only. It's a common mistake made by the best.

I fly with the handle upside down, so I can't say how you should hold your hand, etc. The advice to fly all of the laps as if they were being judged is very good advice. I suspect judging the wrong set of inverted laps is the most common judging mistake. Flying all intervening level laps precisely is a very good idea. They are not judged, but the judges cannot help seeing them.

I would like to add that level flight upright or inverted is a trim issue. If the model is built straight (all incidences to engine thrust line at 0 degrees ) and the model's weight balance ( CG ) is close to the Aerodynamic center, you will have an easier time maintaining stable level flight as there will be less tendancy for the model wanting to change orientation into and out of the wind.

One very important adjustment, is to assure that the flap neutral and the elevator neutral are set together. This can be hidden somewhat with elevator "slop". But, while elevator slop (introduced either by wear or intentionally enlarging the elevator control horn hole )can improve or eliminate "hunting" there can still be a slight varriation in neutral between upright and inverted that can make level flight a conscious effort instead a normal condition.

Another consideration is the stability introduced by the moment of inertia of the spinning prop. A slightly larger prop or a smaller lower pitch prop spinning at a higher RPM can change a model's directional stability. It can also mask other trim problems. In general because we force the model to constantly turn in a circle there is a precession induced force on the nose of the model to lift it in normal level flight and to force it down in inverted flight. In some design discussions, it is suggested that giving the stabilizer a slight ( 1 - 2 degrees ) of positive incidence will make a models turn more uniform between inside and outside. This will also have an effect on the feel of stability between inverted and upright level flight.

Another consideration is the handle setup. Up and down line verticle spacing and neutral hand position can be changed to find you natural neutral position. I've been flying several models lately and adjusting the handle and line combinations to fly with the same natural neutral is essential to be able to fly with consistency. Sure, if you fly only one model, you can program your muscles to adjust to almost any setup; but try flying two different models back to back and you'll see what I mean. This makes the difference between flying the model and the model flying you. (By the way Dirty Dan, this is the only reason I've been able to outscore you in the last couple contests. You keep trying to switch between the Ziltch X, Oriental and Impact while I only have to worry about the Shark and Impact ).

The issue that I have with inverted flight (or level flight, for that matter) is that very, very few folks fly at 4-6 feet.

I'm 6 foot and an inch tall. I figure that if I am looking up at a performance of either level flight, the flyer flunked...simple as that, unless the field is unusually pitched.

4 foot is low....

Although I think that videos pretty much suck as judging aids, dollars to donuts if the video shows the bottom of a guy's aeroplane during level flight, or the top during the inverted portion, the flyer is flunking level flight.

As a judge, I try to count the number of laps aloud...it helps with both a "start" and a "finish" point....

See Ya

My first step in adjusting neutral is to set the handle so the airplane does level flight at the same altitude, both upright and inverted. This cures the flying too high inverted for me.

I've found exactly the same thing Jim. I was surprized how biased I was actually setting up my handles, we make allot of unconscious compensations some of which hamper our performance.

>My first step in adjusting neutral is to set the handle so
>the airplane does level flight at the same altitude, both
>upright and inverted. This cures the flying too high
>inverted for me.

I did exactly the same thing...figured that adjusting the handle by how the model grooved upright/inverted would make it right. When PW picked up my handle at the Wright Bros. Centennial Stunt Clinic & Contest, he said right off that he couldn't fly it with that much handle bias. We changed clips and cranked the eyebolts until it was somewhat close by PW's eyeball, and it flew a bunch better. Inside and outside corners are close to the same size now. If they are not, keep adjusting the handle, or come to the next WBCSC&C. Steve

Biggest help that I've found is to take a sport plane, take off, and fly it inverted for the whole flight. Just go round and round making the airplane go up and down a few times per lap, then hold it level, then do it some more. Much like flying upright, we know what does what, but that doesn't exactly make it instinct. To fly really nice inverted laps, it needs to be instinct. I genenerally don't have any problem getting the model down to and sometimes under 2 foot in altitude while flying upright. Can't convince myself to do it inverted though. More flights inverted would take care of that.