Short Field Takeoff and Flaps

dtreid

New member
What is the best procedure for a short field takeoff with the Cruisair?

I have 4 notches of flap, while the manual only talks about 3. Is the 3rd notch ever used for takeoff or just landing?
 
dtried, my own Cruisair feels like it has 4 positions, but the first click does nothing. It is actually just an over-shoot of the zero flap position. Probably from 65 years of wear. I understand that some owners have filed a 4th position into the piece that controls the flap angle, but I doubt it is any improvement. As far as the third notch for take off, go up to altitude and simulate a go-around with full flaps, and you will soon learn why the recommended take off position is 20 degrees(second notch), not 45 degrees(third notch). You will have very anemic climb, if any. It is a fun thing to practice(or try) , just to watch the VSI keep going down. ______Grant.
 
Grant is right. Zero or first notch for normal take off. 20 degrees " for quick lift off" eg short or soft field.
People have crashed trying to climb out with 20 let alone 45 degrees, when they forgot.

If you try a go around with full flaps - on a LONG runway with no hills/ obstacles.. you will see that you will be barely climbing at near std density altitude.. and really in an unhappy place if it is warmer or more humid. 20 lets you climb, but you will be wondering what is wrong.. same as if you forget to raise the gear.

For short field: Set 20 degrees, brakes and full power, release and hold just enough backpressure to lift you off early,
accelerate in ground effect to a safe speed, establish climb speed ( Vx or Vy) and angle dictated by terrain, reduce flaps to first notch, use best rate of climb when clear of obstacles, raise gear and establish cruise-climb as safety dictates.

This gets busy and awkward but you get used to it. :)
 
My 3rd notch of flap is probable about 25 or 30 degrees. The guy I bought it from always used that for landing rather than the last notch. I guess I was just wondering if I might get better short field performance with it but it looks like definitely not.

Took off tonight with 20 gals of fuel, and myself. Density altitude was about 5500ft on a grass strip. She used up probably about 1300ft. I suppose that is not too bad considering the hot humid evening.
 
I think you will see that our owners manual (we dont have a POH) says normal take off is 20 degrees, and 10 degrees for best rate of climb. I have ridden with folks that never use flaps on takeoff, and I have ridden with a fellow that pulls 20 degrees just at lift off speed. I trust the book numbers on this and get a hundred or more feet before I drop it down from 20 to 10. The single most dramatic difference in takeoff distance was going from a 74-66 wood prop to an Aeromatic. That made a wonderful difference. I have done simulated go-arounds with 45 degrees, and consider that as almost suicide. Proper speed makes things work much better. It is nice for us old guys that best rate of climb, best glide, and flap speed are all within one mile an hour of each other, so it is easy to remember. ______Grant.
 
what my cruisair book says about 20 degrees is " for best take off".

Which is sort of ambivalent. It pretty clearly means for earliest lift off.

But it sure doesn't mean best climb out... or if so, only very briefly

Just as best rate of climb means just that .

The flaps are vulnerable to crap thrown up by the wheels... such as rocks and mud.
One could get very animated on a really rough field take off:
making the initial run to about 30 mph with flaps UPto reduce drag and damage to the flaps
flaps to 20 ( quick like a bunny) and some back pressure for earliest lift off ( remember that mud ?)
accelerate in ground effect to 70something ?
start climbing and quick like a bunny again reduce flaps to one notch 6 degrees in the transition
while establishing 85 Vy
all the while maintaining correct pitch AOA Speed and Directional Control
watching for traffic and the X wind turn

Such are the ergonomic delights of the cruisair, as you half bury your head in the
panel each time you reach for the flap lever.

And they flew these IFR ? :oops:
 
IFR... oh sure.. great airplane.. I was just visualizing a bunch of head motion for flap lever manipulation on
an IFR take off... but I am strictly a VFR pilot and know zip about flying IFR.. less than zip ! :roll:

Imagine guys flying a C-150/152 in Real IFR.. with no wing dihedral. Not my idea of a stable platform in turbulence.
 
I happened to look at the little flap position plate located by the gear handle. It shows 7, 12 and 42 degrees of flap. Does this mean that my 3rd notch is in fact 20 degrees?
 
dtreid said:
I happened to look at the little flap position plate located by the gear handle. It shows 7, 12 and 42 degrees of flap. Does this mean that my 3rd notch is in fact 20 degrees?
Here's a thought: get out a protractor and measure it.
 
you've got a plate showing flap positions ?

anybody else got one ? ?

too lazy to read my manual.. but 12 degrees is not ringing a bell for 2nd position.

I've got an initial click that is no deflection... previous owner told me this was "added"
by some previous owner... but now I'm thinking it isn't..

anybody else go this ?
 
blimpy said:
you've got a plate showing flap positions ?

anybody else got one ? ?

too lazy to read my manual.. but 12 degrees is not ringing a bell for 2nd position.

I've got an initial click that is no deflection... previous owner told me this was "added"
by some previous owner... but now I'm thinking it isn't..

anybody else go this ?
With the potential for people fooling around with such things as flap positions over the years, IMHO the only way to be sure of any one ship's characteristics is to measure it.
You can jaw-jack all you want about the "manual" and tribal lore, or you can get-er-done.
 
My ’46 14-13 had the plate showing 7, 12 and 42 degrees as well. 7 for takeoff, 12 for landing and 42 to add drag for a steeper approach. 7 deg gave me a very small improvement in climb at Vx but less at higher speeds and no change in stall speed that I could measure. 12deg reduced the stall speed 5mph. and the full 42 did help you get down but did not change the stall speed.
 
Now I am really curious. Where is this flap indicator located? Is this something that is only on the original straight 14-13s? I dont doubt anyone, but having poked my head in probably 40+ Cruisairs , over the last 20 years, I have never seen a plate like what is being described. Another Bellanca mystery. ______Grant.
 
No mystery......On my Cruisair,the flap plate is immediately to the rear of where the flap handle comes out of the floor.
And it says "7-12-46" with no mention of takeoff or landing.
My airplane also has an extra notch at about the 30 degree position.
In my experience, the 12 degree notch was best for short/soft operations.
Dan
 
plenty of pilots on here with decades of time in cruisairs..
compared to my spit in a thimble.. that being said it's my opinion
that 20 degrees ( second notch) will get you off the ground quicker..like it says in the manual..and in stances where that is necessary ( soft maybe rough fields) that's what it's good for.

Soon as your airspeed approaches Vy..that much flap extension is just more drag.

I frankly don't know what Vx is..since it's not published...and most judged by not hitting stuff.

Cleaning up the ship fast, and flying the hell out of it tends to work.
Otherwise , mark out a course, get a helper in the cockpit to watch the landmarks, and record the results, then experiment...see what she'll do.

Langewische lists the Zoom as a legit maneuver.. which favors going fast as you can in the reduced drag of ground effect...climbing out with a single notch, and using that money in the bank the way conditions dictate.. if best rate does it nifty, if you need to nibble into your margin above stall to use best angle.. you got a nice little boost.

when in doubt I FLY WITH BOB NEWHART WHO SAID " JUST DON'T"
 
To add to the confusion, I was going through box,s of parts today and ran across a flap placard that I had never seen before. It reads 7 degrees, 12 degrees, 23 degrees, 46 degrees. It appears to be an original piece, but is 4 position. I wonder how many other things dont match the TC or the owners manual. You just have to love airplanes that are old enough to be on Medicare. _____Grant.
 
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