clippwagon wrote:

Terry wrote:1skywagon...2skywagon....3skywagon.
1maule...2maule...3maule.
I just figured out why those Maule's get off the ground quick.....it's a short word?

Dang, I thought it was because they were so ugly the ground repelled them!

CW

clippwagon wrote:Dang, I thought it was because they were so ugly the ground repelled them!

contactflying wrote:Grassstrippilot,

I used several different 150s, 152s and 172s on the pipeline and they are not standard or dependable on how much flap you get without looking where you don't need to be looking. I just set the flap one notch or ten percent before adding power and kept the stick full back until the nose wheel came off. I held the nose wheel just off until the mains came off and then pushed over hard to stay in very low ground effect. The difference in six inches and six feet extra ground effect acceleration rate is tremendous. Like spraying in the crop field, it is important to proactively and dynamically move the wheel/stick fore aft slightly to stay ahead of the airplane. If you just hold the wheel, you will invariably get climb or descend.

The same fore/aft stick technique is necessary to stay in low ground effect with a tailwheel airplane.

Another important technique with crooked runways or departure zones or laterally limited obstructions is to maintain wings level in low ground effect while pushing the nose around with rudder, a skid, to miss the obstruction laterally. We crop dusters never attempt to go over anything we can rudder turn around in ground effect. The common habit of pulling up and putting a wing down to turn before plenty of maneuvering speed is achieved is dangerous. It often gives up the free energy of ground effect prematurely. Once that wing goes down, we can't regain ground effect unless we level the wing. I cartwheeled an A9 Callair and walked away. Spray planes are designed to crash, however. I broke the right wooden spar twice and knocked the engine off.

I can't scientifically explain why, but hitting wind shears and gust spreads in low ground effect always take us sideways, as the other pilot mentioned. I think the hard cushion in low ground effect prevents descent, unless very slow anyway. You would think that in the crop field at greater than cruise speed (because of ground effect) we would sometimes balloon. In 17,000 hours, it never happened to me.

Rapid acceleration is the key to getting off short when heavy and/or at high density altitude. The engine, with less fuel air mixture (lean to peak) can't help. You may already be at ceiling where there is no excess engine thrust for climb. In this case, attempting climb is the most dangerous thing you can do. That is why we always want to know which way is down hill and how we might get there in ground effect, if possible. This is often possible in the high desert and mountains because of the lack of vegetation. Airplanes accelerate well with the nose wheel off or with no angle of attack (tailwheel up and fuse level). They accelerate even better with no ground contact in low ground effect. This is why the test pilot records the max speed when in low ground effect over the beach.

Zzz wrote:

Grassstrippilot wrote:Great video!

I'd like to hear their thoughts for the nose wheel and electric flap drivers. Not all of us have Johnson Bars unfortunately.

That's a good point, but unfortunately that's the downside to electric flaps: It's hard to "pop" them on due to the slower response.

handsrdirty wrote:When I was flying a C206 and needed maximum take-off performance I would roll on full power with 1 notch of flaps, then after getting positive acceleration, 2 or 3 potatoes, put in the second notch of flaps. (I dropped the lever all the way down and then move it back up to the 2nd notch, easier to do without looking) The motor deployed the flaps at a rate that seemed just right for the TO roll. It's not so much pop the flaps as it is reducing drag for initial acceleration, then adding the extra flap and having them slowly come in and the airplane starts flying.

Now I'm flying a Highlander and pop the flaps for every TO. I start the TO roll with no flaps, get some acceleration and pull full flaps. My thinking has been that no flaps have less drag for initial acceleration. I'm going to try starting the roll with 1 notch like in the article, it probably adds very little drag and will help get the tail flying sooner.

This is a great article, thank you to the author, editor and everyone on this site, I've gotten a lot of good information since I signed up a few months ago. Guess I'll quit freeloading and make a donation to help keep it going!

Terry wrote:I also horse it off with lots of elevator and flaps if I need to get off the ground early.
I would like some input from others on this, when we horse it off the ground it's mushy with lots of drag.
So if I'm on solid ground trying to clear an obstical I think it's better to stay on the ground longer with less drag?

contactflying wrote:Your instructors were right about smooth and steady on a long runway in a light airplane. What Patrick is teaching is for short, tight, high, heavy, obstructed, and otherwise marginal environments. Your instructors might also say, "You don't have to go there," and that would be right as well. If we choose to go there, we want to consider every energy source and how to get the very most out of that which is available. Like ground effect, full power given up for a portion of the takeoff run cannot be recovered. When we think we don't need some form of energy, according to Murphy, is exactly when we will wish we hadn't left it unused.

Few of these techniques are taught in the regular curriculum because the government thinks people who know more than they know are dangerous. Inside the box is a major curriculum objective for them.

Pundy wrote:Thanks for the great videos Patrick, there's some great info there. I wanted to ask about your throttle advancement. It may be the video speed, but in each shot where you're pushing the throttle forward, it seems pretty quick. I've always been chided by my instructors to be smooth and steady (i.e. somewhat slow) when advancing the throttle. Any comments you'd like to share on this subject?