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Part 3 will be short and sweet.. and get us that much closer to the first, shared cockpit, checkrides  


Again.. like most landings.. most take-offs should be looked at as short-field take-offs. You always want to get the wheels off the ground, and get space twixt you and terra-firma, as soon as possible.

However... when there truly is a line of trees to clear, and your plane might be heavily loaded.. there are specific techniques involved. Like anything else, there are compromises, and short-filed take-offs take away some of your margin for error, in the areas of controlability and departure stalls. Ideally, you'd never put yourself in a position to be REALLY pondering performance data.. carefully sticking the tanks and emphasizing that your passengers be honest about their weight (been there, done that), while checking density altitude and confirming the actual height of the trees, and their distance from the runway's departure end.. deciding if you can clear them    .... But it wiil happen... And even if it never does, executing text-book, short-field take-offs, will make you a better, more confident pilot.

1) Extend 10* of flaps and taxi onto the runway in a position to use as much of it as possible...

2) After lining up center-line, and perfect runway heading.. stand on the brakes and appy full power..

3) As soon as you're confident that the engine is happy and the oil pressure is good, release the brakes..

4) Immediately pull the yoke all the way back.. it won't take long for the nose-wheel to lift, so be ready on the rudder pedals..ESPECIALLY after lift-off..

5) When the main-wheels lift, lower the nose and pitch for  Vx (60kias) and use mostly rudder to maintain runway center-line.. (bank very slightly at Vx, as banking re-vectors lift and you're already on the edge of the power-curve)..

6) Hold Vx until clear of the obstacle(s) and then pitch for Vy (75kias)..

7) At Vy, retract the flaps , pitching for Vy after retraction..

Quick note...  A soft field take-off is very similar (when there's no obstacle to worry about, else it's just a short-field take-off). The main difference is that you can (and should) pitch for Vy right after the main-wheels lift-off. This can be fun, because initially, you'll actually be pitching nose-down a degree or two, while in ground-effect, gaining airspeed. At Vy, initiate a normal climb.. at 500agl, retract the flaps.

Yes.. I was expecting these questions     That's what makes this fun.

Let me start at your last point.  The old, climb Vx or climb Vy debate.

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Vx is an obstacle only way to climb. If there is no obstacle, you want to be at Vy as soon as possible. Or as my mentor wanted me to call it (even in a single-engine plane)  Vyse. "PITCH FOR Vyse WITHIN 5 SECONDS AFTER LIFT-OFF", because some day you'll be flying twins.  If you're just out of ground-effect, and at Vx when the (an) engine quits.. you're in deep trouble... even on a 10,000' runway. Vx should only be used for obstacle clearance.


As far as a normal take-off roll for short-fields... You're right in that there wouldn't be much difference in the altitude you'd reach upon reaching the obstacle. The math would prove that.... but there are two important reasons for executing a short-field take-off, in the same manner as a soft-field (the only difference being that you'd pitch for Vy during the soft-field).

1) If you're near MGTW on a hot day.. you'll use up less runway before knowing that you'll be able to climb at all (letting you choose to abort sooner)..

2) See reason 1...   because, like learning to pitch for Vyse (or even confirmimg "gear down" in a fixed-gear plane),  that day will come and it's best that you trained/practiced for it.

I've been reading the C172 POH..

Oddly (contrary to any instruction I've ever received) (weren't you taught 10 degrees for a short-filed take-off?), it calls for no flaps at all, for sort-field take-offs. That would confirm the stability/efficiency deal, but I'd bet it's a liability thing. They'd just as soon not publish advising flaps down, short-field take-offs.

I can promise you two times twice.. that I would use(and have used) 10 degrees of flaps when obstacle clearance is a concern.

This is great discussion.. kinda like what you get at the hangar (what I've been hoping for).. even like the discussion instructors get into, after dismissing the students   ...  "He's  MY student, I'm going to teach him MY way"  ..LOL

There is no right or wrong here (so far)... (I'm more likely to end up wrong, as I emulate my near 80-year-old mentor .. and he's pretty set in his ways, and at odds, more times than not, with the young.. "fresh-out-of-college-aeronautical-degree-in-hand", instructors we get; being based at Ohio State University's airport).

Between the POH, you, and myself...  we've got three different short-field take-off techniques. All three will "work"... and if you're in a position where the difference (if any) would mean clearing, or not clearing the trees... you wouldn't be taking off in the first place. I use/teach/taught my method, because that's how I was taught. The POH would have you believing that a short-field take-off is no different than a normal, no-flaps take-off; except that you'd pitch Vx. That's flat out untrue, and more a liability concern, on the part of Cessna. Your method differs only in that you'd have 10 degrees of flaps deployed. My method is yours, but with the added intention of getting the wheels off the ground and at Vx ASAP; theoretically letting you judge sooner, whether or not a Vx climb will get you over the obstacle (or if the plane will even climb at all.. because in theory, you'd only be worrying about this obstacle stuff, with a heavily loaded plane and/or high density altitude) while there's still some runway left in front of you. How much runway you'd conserve is questionable, I'm sure. But "my" method wouldn't cost you any runway(I think ..lol).

Now.. it is more difficult, and as you asked, "wouldn't that put a beginner at risk of getting airborne at a speed more conducive to a "soft" takeoff? " , the answer is obviously, yes. But every aspect of learning to fly will have beginner testing/learning/proving himself... and he had better be comfy with an airplane, during this technique, before he takes his checkride.

I'm reminded of the A36 take-off and crash video we all commented on, not too long ago. It was a hot issue at our hangar, too. The A36 POH also calls for a no-flap, short-field take-off (like the very experienced pilot tried). There wasn't much contention among our pilots/instructors (including an A36 owner), in that it's pilot discretion, and that indeed that A36 pilot should have used a notch of flaps. Of course, not everyone agreed with me, in that he should have  had those wheels off the ground ASAP. In my opinion... he "might" have been able to clear that knoll, gaining altitude in the more efficient ground-effect... and, if nothing else, he'd have found out sooner that that dog wasn't going to hunt, before dragging the plane down the runway, past the point of no return.

Brett_Henderson wrote on Dec 15^th, 2007 at 11:16am:


Sure... if I were ever in serious doubt, that technique would be best, pavement or no pavement.