Need help with soft field take off

S

skynewbie

Pre-takeoff checklist
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checkmysix
My soft field take offs suck. I have trouble knowing how and when to push forward on the yoke to avoid banging the tail as soon as the nose comes up in ground effect. And tips how to figure this one out?
 
Start with full back pressure on the yoke as you start the takeoff roll. The nosewheel will lift off pretty early in the takeoff roll. Relax just enough back pressure to freeze the sight picture and maintain that pitch attitude. If you push forward at this point, the nose will probably recontact the runway. Your most important metric here is your eyes.

In another 20 knots or so, the whole aircraft will lift off, at which point you will need to relax pretty much all the back-pressure and begin to apply progressively more forward pressure to keep the airplane in ground effect (less than half a wingspan's height above the runway). As you close in on Vx, begin releasing the forward-pressure and resume a normal climb.

If it's any consolation, it's harder to simulate a soft-field takeoff on a paved runway than to do a real one. Perhaps you could get your new instructor to take you to a grass/dirt strip. It is more obvious when the nose lifts off on a rough/soft field.
 
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Awesome advice this really helps! I will plead with my new instructor to take me to a real grass strip to practice this in the Bay Area. BTW another student recently failed his checkride for banging the tail during one of these. I plan to avoid this from happening.
 
I second the advice to try it from grass. I don't think I ever did a GOOD soft-field until I had to do it for real. We were on a "turf" runway that was more like 6" tall thick weeds. That will drive home the real point of the exercise.

"Get the wheels out of the weeds, and finish the takeoff just above the tops of them."
 
DMS gave you good advice. Very well written. Its just a feel and you will get it
 
DaleB said:
I second the advice to try it from grass. I don't think I ever did a GOOD soft-field until I had to do it for real. We were on a "turf" runway that was more like 6" tall thick weeds. That will drive home the real point of the exercise.

"Get the wheels out of the weeds, and finish the takeoff just above the tops of them."
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Third the advice to find an instructor who will let you do this on real grass. Like Dale, I didn't have a good feel for it until I was on the soft stuff.

Same training applies to soft field landings. Simulating it on a paved runway is fine, but doing it for real on grass is totally different, and way more fun.
 
Another suggestion is taxiing with the nose off the ground. Helped me to get the stick and the throttle coordinated.
 
skynewbie said:
Awesome advice this really helps! I will plead with my new instructor to take me to a real grass strip to practice this in the Bay Area. BTW another student recently failed his checkride for banging the tail during one of these. I plan to avoid this from happening.
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Fly on down to Frazier Lake, there's a nice grass strip down there.
 
Aeric said:
Fly on down to Frazier Lake, there's a nice grass strip down there.
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Get approval from the club first. It's a formality most of the time (except in winter when the field is NOTAMed), but your agreement says you'll do it.

And take an aircraft with no wheel pants just in case.
 
If you haven't banged the tail on the ground yet, you probably have a better handle on it than you think. :D
 
The funny thing is, a) my club had a rule against landing on grass (wtf) and b) the 152 I did my checkride in was so underpowered that my DPE claimed demoing a proper soft field takeoff in it was darn near impossible.
 
Keep in mind that grass doesn't automatically equal soft. You can get in some real trouble on shorter fields trying to do a soft field takeoff when it isn't necessary.
 
My PPL CFI had me envision a small tunnel that I had to keep the airplane in all the time while in ground effect. This may help you also. Think of the close walls and ceiling and keeping the plane barely off the deck. This of course is only once you get slightly airborne. The previous advice is spot on.

David
 
Thanks guys! Really appreciate the tips in helping me to visualize how to correctly perform the maneuver.
 
My favorite thing to practice ! I haven't done it on a real soft field but as was already mentioned, my instructor has me pull full back, relax as soon as the nose comes up, hold it until we are flying in ground effect and then push forward to a neutral position count to 3, check the airspeed is at Vx and then up and away we go. Great feeling when done right
 
Problem giving it too much power to start. ease in on the throttle as you feel the elevator take effect. then as you get the feel of the elevator and get control of the nose attitude, feed in more throttle to the full throttle position keeping the nose out of the mud, but dragging or striking the tail.
 
skynewbie said:
My soft field take offs suck. I have trouble knowing how and when to push forward on the yoke to avoid banging the tail as soon as the nose comes up in ground effect. And tips how to figure this one out?
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And you think you're ready for the PP Practical Test? Sorry, Ben, too many things don't add up in your posts. I think you're beyond helping via the internet. You need a competent, qualified CFI to evaluate your knowledge and skills, and then work out a plan to get you ready for the test. Any other advice here is wasting everyone's time.
 
I'm hoping the rain lets up enough tomorrow morning so I can take the 172 "mud bogging" over at Candle Light Farms.
 
You need to experience a dirt or grass strip, teaching soft field on a paved runway is crap.

Tell your CFI what's up, find a strip on the sectional and make a plan.

Not only is this important, most good CFIs LOVE going out to grass/dirt strips.

*Also "banging the tail", really?? Never done it or had a student do it, that's a... impressive feat
 
Ron Levy said:
And you think you're ready for the PP Practical Test? Sorry, Ben, too many things don't add up in your posts. I think you're beyond helping via the internet. You need a competent, qualified CFI to evaluate your knowledge and skills, and then work out a plan to get you ready for the test. Any other advice here is wasting everyone's time.
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oops... been off of the red board for a few weeks... the mental penny just dropped.
 
Ron Levy said:
And you think you're ready for the PP Practical Test? Sorry, Ben, too many things don't add up in your posts. I think you're beyond helping via the internet. You need a competent, qualified CFI to evaluate your knowledge and skills, and then work out a plan to get you ready for the test. Any other advice here is wasting everyone's time.
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Agreed, Ron. Too many different stories between here and the red board. There's always two (or more) sides to an issue, and I think there's a lot more going on than we're hearing from Ben.

Ben...Cap'n Ron has it 110% correct. Get off the internet for now. Find a good CFI and stick with him/her. Listen to your CFI. Get your checkride done. And then and ONLY then come back and give us the news (on both boards) that you've got your PP certificate.


Mike
 
NineThreeKilo said:
You need to experience a dirt or grass strip, teaching soft field on a paved runway is crap.

Tell your CFI what's up, find a strip on the sectional and make a plan.

Not only is this important, most good CFIs LOVE going out to grass/dirt strips.

*Also "banging the tail", really?? Never done it or had a student do it, that's a... impressive feat
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There are some rumors around the club about a tailstrike during a soft field takeoff in a checkride. I would have thought whanging the nosegear would have been more likely. I don't know the details, or even what aircraft was affected. None of them seem to have gone down for tail repairs. I wonder if it might have been a minor one that just polished the tail tiedown loop, or wild pitch control resulting in the DPE grabbing controls to avoid a tailstrike, and a pink slip.

Ben needs to demonstrate a soft field takeoff on a paved runway for his checkride. There are only a couple of public use turf runways in the region, and they are much too far for a checkride. It may be "crap," but it's also reality.
 
Ron Levy said:
And you think you're ready for the PP Practical Test? Sorry, Ben, too many things don't add up in your posts. I think you're beyond helping via the internet. You need a competent, qualified CFI to evaluate your knowledge and skills, and then work out a plan to get you ready for the test. Any other advice here is wasting everyone's time.
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Somebody gets it.
 
MAKG1 said:
There are some rumors around the club about a tailstrike during a soft field takeoff in a checkride. I would have thought whanging the nosegear would have been more likely. I don't know the details, or even what aircraft was affected. None of them seem to have gone down for tail repairs. I wonder if it might have been a minor one that just polished the tail tiedown loop, or wild pitch control resulting in the DPE grabbing controls to avoid a tailstrike, and a pink slip.

Ben needs to demonstrate a soft field takeoff on a paved runway for his checkride. There are only a couple of public use turf runways in the region, and they are much too far for a checkride. It may be "crap," but it's also reality.
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You two in the same club?
 
EdFred said:
Keep in mind that grass doesn't automatically equal soft. You can get in some real trouble on shorter fields trying to do a soft field takeoff when it isn't necessary.
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It's not really "soft field" unless it requires as much or more than runnup power to get the airplane to move. In those conditions unless you use proper short field techniques you might not get off the ground no matter how long the runway is.
 
flhrci said:
My PPL CFI had me envision a small tunnel that I had to keep the airplane in all the time while in ground effect. This may help you also. Think of the close walls and ceiling and keeping the plane barely off the deck. This of course is only once you get slightly airborne. The previous advice is spot on.

David
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Unless it's really muddy or there's more than an inch or two of heavy snow it doesn't hurt much to "brush" the ground with the main wheels occasionally while building enough speed to climb. The loss of ground effect from getting more than a foot or two between the wheels and the ground can lengthen your takeoff more than a few light touches, especially in a high winged airplane.
 
NineThreeKilo said:
You two in the same club?
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Yes. And I've flown all the same airplanes he's been complaining about. Some of the MX issues are potentially serious (I won't fly one of the SPs because of its fuel gauges -- I think its electrical problem is benign, but I'm not sure enough to bet my life on it), but most are the nuisance types (DME, CDI), and some are nonissues (minor but noticeable flat spots on the tires).
 
I've only ever seen a tail hit the ground once, and it was done by the world's greatest pilot on approach to landing....

Are you sure its even possible during a soft field?

On second thought - I saw another one, a very heavy 182, when it came back around, it had scraped the grass and picked some up on the tail tie down.
 
SkyHog said:
Are you sure its even possible during a soft field?
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I suppose it would be if you forgot to pull the yoke back, and then corrected by rapidly pulling back to the stop. But no, I'm not at all sure. Not particularly anxious to test it, either.
 
I witnessed a 172 R or S model scrape the tail across the ground while taking off. I don't even know if it was a soft-field takeoff or not (it was a private pilot on a paved runway).
 
If you keep the yoke pulled back too long on rotation into ground effect without pushing the nose forward the tail will strike. Almost happened to me this weekend on practicing soft field takeoffs which concerned the CFI I flew with.
 
It kinda sorta looks like this...

I'm actually just trying to keep the nosewheel light and play with the STOL kit and 30 degrees of flaps, but the elevator authority is a little better at Gaston's than up here at 5883' MSL. ;)

(In other words, it rotated a bit sooner than expected and quicker, so I let a little back pressure off and just left it nose-up since it was already above the STOL performance numbers for takeoff. There's a dirt bump there I was aiming for to assist with the "launch". Heh.)

David White had been lifting off consistently in White Lightning in his 172 for two days, prior to the windsock, and I knew the 182 would do it... Finally got bored enough to go see exactly where it would come off at. I tossed all the extraneous stuff out in the grass and had about 50 gallons of fuel on board, me, a headset, and the iPad.

Level off after liftoff and wait a bit for a safe flap retraction speed from 30 to 20.

Fun as hell, actually. It takes significantly more runway up here. :)

http://youtu.be/D01jHXn2q28
 
skynewbie said:
If you keep the yoke pulled back too long on rotation into ground effect without pushing the nose forward the tail will strike. Almost happened to me this weekend on practicing soft field takeoffs which concerned the CFI I flew with.
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I'd be a LOT more concerned about a departure stall than a tailstrike under that circumstance. In a soft field takeoff, you're leaving the ground below stall speed and relying on ground effect to inhibit the stall. Leave ground effect at that speed, and bad things happen.

You just need to get it off the ground. As close to the runway as possible.

A similar technique can be used at high density altitude to help the aircraft accelerate without wheel resistance, and thus shorten the otherwise interminable roll.
 
Nate, I thought 182s were "not approved" for takeoffs with more than 20 flaps. Does the STOL STC change that, or were you in test pilot mode?
 
MAKG1 said:
Nate, I thought 182s were "not approved" for takeoffs with more than 20 flaps. Does the STOL STC change that, or were you in test pilot mode?
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The Robertson STOL changes it. Can't speak for the other STOL kits. The POH addendum document adds performance numbers for it.
 
denverpilot said:
The Robertson STOL changes it. Can't speak for the other STOL kits. The POH addendum document adds performance numbers for it.
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P.S. Flap 30 T/O is fun but nearly useless. Note I'd leveled off... and it takes a while to overcome the drag and start climbing again.

50' obstacle clearance is actually worse (takes more distance).

The point of the Robby seems to be to get you off of unimproved surfaces quickly, but climb out performance actually suffers. If you operated from gravel and hated kicking it up into everything, it might be a plus...

Flaps 20 behaves and feels much more stable and normal. You really know you're horsing it off the ground at 30. And way behind the power curve if the engine even hiccups.

Where the Robby shines is landing. It just makes the thing rock solid stable down to incredibly low speeds. Ailerons very positive and the stall fences kinda make a ringing/singing noise as they block more flow, which is a nice auditory backup to eyeballs on the ASI.

In cruise, you can reduce power to idle and then literally just hug the yoke all the way back with both arms and all that happens is a gentle porpoise from flying to almost not flying and back.

I think there isn't much use for that, other than as a demo (ailerons are still effective there too), but if I had to land off-airport in terrain that was particularly inhospitable, I could be about 20 MPH slower than a normal 182.

Might mean the difference between walking away and a stretcher. That's a big difference in force in an impact.

I hate to talk it down because its a barrel of monkeys in the fun department, but practicality of the Robby is fairly low, just by the numbers.

I haven't really got a hard core "mission" for it, it's just the airplane the co-owners had when I found 'em. ;)

It is kinda "OMG, that was cool!" near sea level. Up here it just feels nice and solid in gusts and heavily loaded. Sometimes the normal 182s I've flown felt kinda sketchy at low speeds. Like the bottom is about to fall out.

No feel of that at all in the Robby -- right up until it sighs and porpoises. One of those near the ground would be OUCH time for the gear, so I don't play the "bounce the ASI needle off the bottom peg" game below cruise altitudes. ;)
 
skynewbie said:
My soft field take offs suck. I have trouble knowing how and when to push forward on the yoke to avoid banging the tail as soon as the nose comes up in ground effect. And tips how to figure this one out?
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I can't help you with bumping your tail, that's a matter of 'feeling' the aircraft. You'll get it. Just keep practicing. Sorry I can't help. My tail bumps all the time, because I'm a weirdo and I like bumping tail. :rockon:

But I can leave you with a short field tip. A short field with trees ...

After rotation, aim for the tree tops. You only have to clear them by a few feet. By the time you reach them, you should have lift and speed to spare for a pull up. Chances are you'll be way above them already... :yes:
 
SkyHog said:
On second thought - I saw another one, a very heavy 182, when it came back around, it had scraped the grass and picked some up on the tail tie down.
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Which was the basis for my previous comment in the thread.
 
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