Greetings! I'm new to the forum...been lurking around for a while and already seem to many of you My home base is Red Lodge, MT. I fly a 1980 C182Q. I saw this take off (see YouTube link below) and wondered what your take is on dropping the flaps just before rotation on a short field takeoff. It's not the way I was taught to do short field takeoffs, but maybe it's a valid technique. What say you??

http://www.youtube.com/watch?v=16gxloNo_Ck

I think thats a good technique to use if you screwed up and forgot to put a notch of flaps in before starting a short/soft field takeoff...

i think the pilot put the flaps down to late. in grass with the flaps up it puts more weight on the tires causing more drag than it would be with the flaps down. in an 182 i would be more worried about keeping that training wheel off the ground so you don't find that one Montana gopher hole. if you want to try something new go out with a CFI on a grass strip and she what she will do

I agree. I soled back in 1974 in a super cub and flew taildraggers for a few years. When I stated flying cessnas, I was thankful for tail dragger time, cuz it taught me a lot about proper landing technique. In that clip it doesn't look like he had full throttle with the brakes set either and wasn't using much back pressure on the yoke. Kinda had me pukkered a bit watching it.

MTPilot wrote:I saw this take off (see YouTube link below) and wondered what your take is on dropping the flaps just before rotation on a short field takeoff. It's not the way I was taught to do short field takeoffs, but maybe it's a valid technique. What say you??

It is a great technique especially if you have mechanical flaps. I used it all the time when flying my previous Maule, C170 and C182s (1958 model) off short strips. I don't use it with my Husky as the Husky gets off the ground at such a slow airspeed that the drag of full flaps on initial ground roll is not a factor. I just put in full flaps and go with the Husky. But on my previous other planes, on short strips, I would start with no flaps and then pull on the flaps when I felt the airplane would fly. By using the mechanical flaps, you can pull on as much flaps as you need, but then bleed them off once in the air and the nose is down and airspeed increases. But be careful in gusty winds as you might lift off at a slow speed only to find your plane settle back down to the ground if you use too much flaps (excessive drag), don't lower the nose to pick up speed, or if the wind on the nose suddenly decreases (or a combination of the above).

I'm not sure I would want to use this technique with electric flaps, but must admit that I haven't tried it. The mechanical flaps put the control in your hands, but you do need to practice it. It does add another degree of coordination to the takeoff process.

I never lock my breaks while adding full power.

That's a good point about mechanical vs electric flaps. Personally, with my plane not having mechanical flaps, I'm not sure I'd use this method, but I see your point!

I don't fly trigear aircraft much but my pocket book wouldn't survive too many takeoffs with full power and the brakes set in the dirt in T/D mode much less a nose dragger. I'm too cheap to land anywhere that short I guess. This argument comes up every year at the ag convention, big draggy flaps on most of the birds so some guys say it helps. Other side of the coin is what are you going to do when they don't come down and you had a load on that you need them for. Too pricey for my blood again. I have used it in a cub and 180 but mostly just messing around where it wasn't really needed.

I can't access the link, so I'll only comment on what you asked in your post.

I think it's a valid technique, more so with manual flaps and a "Johnson Bar", than electric flaps. Trying to select the proper amount with the electric flap switch while bouncing down the runway, and then the need to look back inside and verify, while possibly hitting a bump at the wrong time and and going to 40 degrees, not a good thing, can be challenging to some. However, with the Johnson bar, they are quicker to deploy and easier to time and get the exact amount you are wanting for the situation. Simply reach over a pull two notches in, and your good to go. There is no need to look back inside to verify, you can do it by feel, and is much simpler for most.

We also need to distinguish between short and soft field technique or, as a practical matter, a combination of the two.

Of course like many things, when and where to use it "depends". Obviously, the theory is less aerodynamic drag without any flaps deployed, giving quicker acceleration, for better short field performance. Just before reaching the desired speed, you "pop" a couple of notches of flaps in and literally jump up into ground effect. Timing is everything, and with experience, it works very well, when the conditions are right.

Now the "depends" part also matters on what type of runway, soft or firm, long grass or short grass, potholes, ruts, pilot's experience/ability etc,...... With long grass, soft ground, potholes or any other need to get weight off of the mains as quickly as possible, then it probably isn't the preferred technique.

OTOH, If the pilot is comfortable with managing all that goes along with deploying them during take-off from a short runway, then yeah, it will help shorten the take-off roll under the right conditions.

That was definitely NOT a short field TO!

That airplane has electric flaps as well. How come they are not down first? Does not look windy. Maximum performance in that machine is 20 degrees flaps. They need to be down prior to the roll. Also looks like a soft field and the nose never comes up. Unless he was a max gross, he had a huge ground roll prior to the nose coming up.

Having almost 2000 hours in my own 182 that was a poor display of a short and soft TO.

Again, 20 degrees flaps, full power, full brake, then let off, yoke in your lap and your off the ground in under 800-1000' depending on your weight. With a head wind its less but again the 20 degrees flaps is still your maximum performance setting. Wether you like flaps or not in windy conditions is up to the pilot. Crosswinds, maybe not so much if you choose. Straight down the runway, apply them.

My 180 is a different beast that I am experimenting with adding the flaps to the roll, but seems like I like them prior to the roll as well. Cross winds are a different story.

Just watched that one again. Its a very poor technique!

He does look very heavy. 4 people plus fuel, I am betting he is close to gross depending on how much fuel he actually has on board.

That guys nose should be off the ground before he is even close to that puddle. No matter what his gross is given the distance of the roll he has there.

Just watched the video.

Looked Ok to me, maybe put the flaps in a hair early. And could have possibly stayed in ground effect a little longer, accelerating, before turning and sinking before lowering the nose to arrest the sink.

Holding the brakes with full power does nothing for performance, just picks up everything on the ground around you and eats your prop. Very Poor technique.

Holding the yoke all the way back is also unnecessary and very poor technique with a firm runway. Looked to he like he had a pretty firm runway. Albeit, with a few shallow puddles that didn't appear to slow him down. Holding the yoke back unnecessarily creates drag, drag reduces acceleration. Not good for short field performance.

Didn't look like using a "soft-field" technique was necessary in this case.

All in all, looked pretty reasonable and effective to me, I'd fly with him.

I was taught to use the flap handle technique and now that I have a taildragger with electric flaps, I use a variation of the flap handle technique where the flaps are fisrst set to the angle of the deflected aeleron. Once I accellerate and the plane is just about ready to fly I will drop the flaps 10 -15 more degrees and push the nose over. Once the plane is climbing, the flaps are then fully retracted. This method gives me the shortest takeoff roll in my plane. I really miss manual flaps.

I've been playing with the manual flaps in the 172 and really think I can get off the ground shorter by popping them once the gear starts to feel light so to speak.

In this case, getting the nose off early would have reduce nose drag and protected the gear and prop but back elevator is also going to add some drag.
I haven't played with mine enough to determine if I'm off shorter without back pressure or by getting that nose off the ground.
The electric flaps certainly didn't pop him off the ground. He probably would have been better off putting in a notch before starting his roll.

I hope that takeoff was at about 10,000 MSL, that's a ground loving machine there. There's no reason to go to full power with brakes locked. You don't gain anything.

WSH-

Really... a mud puddle in the middle on grass and dirt strip is not soft? Granted this one does not look mushy but, its definitely not paved.

Yoke in the lap is a must in that technique. Even more so with the 182.

Not so certain about the full power run up with full brakes given the length of that runway shown, but if it were short the extra 5-10 feet you gain from full brakes with power is what I have always been taught (from those that fly in and out of the bush daily) rather than powering through that space running up. Also, for a short field TO, just look at the VDZ STOL contest or any of the big rks lng prop videos. Every one of them are full brakes and power prior to running down the runway.

You would only use as much yoke as necessary to lift the front wheel the minimum amount necessary for the current conditions performing a "Soft-field" take-off. Anymore creates unnecessary drag, which hurts acceleration. The strip in question didn't look "soft" or have long grass from what I could see. So holding the yoke back would only increase his ground roll without adding any benefit and in this case, IMO, be very poor technique.
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I've run though "puddles" on 9000 foot runways before, do they require using a soft field technique too?

Your mistaken about the "locked brakes" and full throttle. I'm willing to bet nobody here, or anywhere else, with any experience does it, as matter of practice. It may make you feel good, but there is no increase in performance, advantage, from doing it. To me, it's a sure sign of inexperience and lack of technique.

Tell you what, I'll go along with whatever MTV says about the subject.

I guess we need to agree to disagree....

This 'technique' is 100% aircraft and load dependent. Since there are many different types of wing, flap, load combinations there is no one size fits all.

Having said that, I would say that take off probably demonstrated exceptional form based on the little info we have. Bare in mind this is the 'real deal' not some feather weight, big rocks long props, a'la vadez, hocus pocus...

1) an air ambulance with 4 up and probably full fuel, IOW, max gross ++
2) Venezuela, strictly a guess here, but probably a mountainous region of higher DA (although it very well could have been a costal hill top)
3)flaps too soon, or flaps too much = Drag. Drag plus a uber load = Bad
4) soft field practices... you do not get extra credit for soft field work. Either you need it or you don't, and like flaps, elevator = drag. You need it, you use it... but if you don't need it, the use will cost you, there are no free rides...

The technique here looks only slightly modified from the MAF departure,which consits of a flap jump to 2" agl and then a bleed off in ground effect to a safe speed. Most likely only modified because the 'flap jump' is awful hard to execute with slow Cessna electric flaps.

My preference is to feel the airplane get light before any major flap app, and then bleed them off while gaining well beyond a safe flying speed in ground effect.

It is also my preference to use as much of that ground as I have to. And since it is not Valdez, there are no points for lumbering a patient, and medical help into the air with less than adequate flying speed. Having said that, I would have to say that this 'technique' fits my mission (which generally involves my wife, a friend, or a kid) far more so than a technique geared more towards using less terra firma ... again, not a one size fits all... I do enjoy a lot of short, tight area's, but generally speaking I'll use what I have, rather than what it takes...

Coincidentally, not only do I utilize somewhat of a 'flap jump' in my cub and 180, I also do it in my work plane, which has electric flaps. Having literally thousands of take offs a year from the same strip I am certain that it will leave the ground just fine with either pre set flaps, or a flap jump. However, I am also 100% certain that if I start with flaps up, drop flaps when the tail gets light, and bleed off as able, I am always faster, sooner. And in that application faster is better...

Take care, Rob

I guess these guys have no experience...

http://www.youtube.com/watch?v=Vm3kH5t5CCM
http://www.youtube.com/watch?v=-aGolOOo ... re=related
http://www.youtube.com/watch?v=bPSElw8q ... re=related
http://www.youtube.com/watch?v=8RQGSVf- ... re=channel
http://www.youtube.com/watch?v=H-Mqau9V ... re=channel
http://www.youtube.com/watch?v=zbozrPXhGNw&feature=fvsr

Not to mention from the Syllabus that you should have followed when getting your private certificate:

Short Field Takeoff practical test standards

Short field takeoffs are utilized when it is necessary to get off the ground in the minimum distance and climb relatively steeply to clear obstacles. Many trainers such as the Cessna 152 call for use of 10 degrees of flaps for the short field takeoff. Once pre-takeoff checks are complete, set flaps as appropriate prior to taxiing onto the runway. Taxi onto the runway and stop at the very beginning of the runway so no distance is wasted.

While using your toes to apply the brakes and hold the airplane in position gradually add full power. Check the engine instruments and tachometer for normal indications prior to releasing the brakes. In a real short field situation, it’s important to know the airplane is developing full power before attempting to take off with a short runway or obstacles to clear. Hence the run-up to full power prior to brake release. The run-up also prevents wasting runway while you add power. Assuming all indications are normal, release the brakes and accelerate down the runway to rotate as normal and commence a climb out at the recommended obstacle clearance speed or best angle of climb speed, Vx. This will be a more nose high attitude than you have used previously and you will need to be attentive to precise airspeed control. Also, because of the high power setting and high angle of attack, you need to use plenty of right rudder to overcome left-turning tendencies. After clearing obstacles, lower the nose slightly and accelerate to best rate of climb speed, Vy. With a positive rate of climb established, retract the flaps and continue the upwind climb as normal.

In a real short field situation, be particularly attentive to maintaining the correct airspeed. Only the recommended obstacle clearance speed, or Vx, will give you the best angle of climb. Anything faster or slower will not work as well.

AND WHILE WERE ON THE TOPIC OF TAKEOFFS: HERE IS SOFT FIELD TECHNIQUE FOR YOUR REVIEW:

Soft Field Takeoff and Landing techniques are good skills to have even if you have no intention of exposing yourself or your airplane to the challenge of a real soft field. Most people will learn these techniques on a regular paved runway and seldom, if ever, get to put their skills to work on a real soft field. However, you will definitely be tested on this as part of the private pilot practical test and, in the event of an emergency landing off airport, you will be glad to have this skill available.

To develop your soft field technique, visualize mud. Your objective is to maintain directional control and not get stuck. With just three small wheels and a propeller to work with, this could be challenging. Fortunately, all of your control surfaces can be of use in keeping things rolling and pointed in the right direction. Before you start your taxi, get organized and complete all necessary pre-takeoff checklists so, that at least in theory, you can keep rolling all the way to the runway and take off without stopping. Because of constraints imposed by control towers and crowded tie-down areas etc., you probably will not get to practice this part. A real soft field taxi will require more power than usual to get started and probably more than usual to keep rolling. In a tricycle gear airplane, taxi with the control wheel held all the way back to minimize weight on the nose wheel. The nose wheel is the most likely to get bogged down, so do what you can keep it light.

In many airplanes such as the Cessna 152, the soft field takeoff is performed with 10 degrees of flaps extended. If flaps are to be used, extend them as you taxi onto the runway. In a real soft field situation, tower and traffic permitting, you would taxi onto the runway without stopping and, once lined up on the centerine, apply full power with the control wheel still in the full aft position. You want the nose wheel to come off the ground at the first possible opportunity, but not so swiftly that the airplane rears up and scrapes it’s tail on the ground. Most trainers have a tail tie down skid installed to lessen the consequences of scraping the tail. As you add power and accelerate, airflow over the elevator will increase and it will become more effective at raising the nose -- so much so that you will probably need to reduce the backpressure on the control wheel slightly to allow the nose wheel to lift off without the tail scraping. As you add power, you also need to add right rudder to prevent your airplane from unexpectedly exiting the runway to the left due to normal left-turning tendencies that are at their most noticeable in high power/high angle of attack situations.

The idea is to get unstuck from the runway at the first possible opportunity and then build up airspeed in ground effect before attempting to climb out. So, you accelerate down the runway with the control wheel positioned further back than for a normal takeoff. The nose wheel will lift off first and, as you continue to accelerate and maintain directional control with rudder the main wheels will lift off. This happens at a lower airspeed than for a normal takeoff and below the speed at which it is safe to climb out. As soon as all three wheels are off the ground, move the control wheel forward to lower the nose into a straight and level attitude. This allows the airplane to build up more airspeed in ground effect before attempting to climb out.Lowering the nose at this point takes some willpower, since it is not intuitive to lower the nose immediately after liftoff when very close to the ground.

It is important, however, that you do not attempt to climb out of ground effect until your airspeed is at least at best rate of climb speed, Vy. For the purpose of learning/demonstrating your soft field takeoff technique, if the runway environment permits, you may fly along in ground effect a little longer than is strictly necessary. Contrary to what every bone in your body is telling you as you try this the first time, you are unlikely to fly yourself back into the ground unless you are really heavy-handed and not paying attention. You may be heavy-handed but it’s safe to say you’ll definitely be paying attention during this challenging task. Once the desired airspeed is attained, pitch to begin your climb by applying a little backpressure; then climb out at best rate of climb speed, Vy. Once a positive rate of climb is established, retract the flaps and continue the departure as normal.

This should be a good one!

GB