Slipped takeoff

Jaybird180

Jaybird180

Final Approach
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Jaybird180
Much discussion regarding side slipping on landing in crosswinds, but who side slips a crosswind takeoff?
 
Everyone who does it correctly. Otherwise, you skip across the runway on rotation.

It's not necessary once the wheels leave the ground.
 
I don't know for sure what you are talking about, but crosswind takeoff procedure is full aileron into the wind as you begin the takeoff roll, gradually easing off until liftoff, at which time you will be wing low on the windward side but will immediately transition to a wings-level crab into the wind. Rudder to keep the airplane's motion parallel to the centerline is a given.

On landing the process is reversed, with full aileron into the wind as you slow to taxi speed.

Bob Gardner
 
Exactly. It's a transition move. You don't want to keep it in a slip because that just adds drag.
 
Jaybird180 said:
Much discussion regarding side slipping on landing in crosswinds, but who side slips a crosswind takeoff?
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No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
 
CTLSi said:
No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
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Oh give it a freaking break.

While uncoordinated may decrease your takeoff performance, being uncoordainated does NOT call stalls. As I keep trying to explain to you, the ONLY thing that causes stalls is exceeding the critical angle of attack.

Cross control is not the definition uncoordinated either. In fact, climbout is one of those places in the flight regime where you may indeed be cross controlled. You may indeed need to hold right rudder in a climb while banking to turn left.

If cross control or being uncoordinated caused stalls and crashes just about every student out there wouldn't survive his first lesson.

CLARK and MAKG gave the right answer. Unless you have crosswind gear (and even then it's probably not advisable), you HAVE to be in a slip or else you're going to drag your tires or you're going to not track the centerline. Once the mains come off, yes you want to release whatever rudder you're holding to track straight and start crabbing into the wind (usually all that is necessary is to remove pressure from the pedals) and then put in whatever right rudder you need to maintain coordinated flight.
 
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My focus on a crosswind take-off is a positive rotation. On a normal take-off I use back pressure sufficient to get weight off of the nose wheel as early as possible. Doing the same in a strong enough crosswind can mean skipping across the runway.

Crossing controls won't make you stall, crash and burn. In fact if we start the roll with ailerons full into the wind while we steer down the center line we are beginning with crossed controls.
 
CTLSi said:
No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
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Simply untrue. A cross controlled takeoff is not normal technique, but it does not result in "stall and crash" unless you stall it and crash it. Many airplanes will happily climb under full takeoff power in a slip at a safe airspeed. Yours included.
 
Here in Mammoth with only 100hp no take off is assured. If wind shear is abundant I prefer to be aligned and track the center line in case I'm going to need to use the runway in front of me.
 
CharlieTango said:
Here in Mammoth with only 100hp no take off is assured. If wind shear is abundant I prefer to be aligned and track the center line in case I'm going to need to use the runway in front of me.
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Eh? I learned to fly on the front range of the Rockies with a 152. I'd prefer to be climbing at the maximum performance to get away from the ground. I've got no problem kicking her straight with rudder if I end up having to put her back down on the runway just as when I'm landing. Tracking the center line is something you do even when flying coordinated.
 
flyingron said:
Eh? I learned to fly on the front range of the Rockies with a 152. I'd prefer to be climbing at the maximum performance to get away from the ground. I've got no problem kicking her straight with rudder if I end up having to put her back down on the runway just as when I'm landing. Tracking the center line is something you do even when flying coordinated.
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Wind shear here can be a big issue and until I know that I can establish and maintain a positive rate of climb I'm concerned about my orientation with the remaining runway.
 
I still don't know what wind shear has to do with it. Once you've got enough airspeed to get the wheels positively off the ground (and yes in gusty conditions or possible wind shear I hay keep her on the ground longer), it's unclear why you're doing that. Once you're positively off the ground FLY! Keeping the longitudinal access aligned with the runeay does NOTHING to enhance safety.
 
CTLSi said:
No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
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The quality of your troll posts is slipping.
 
Failure to turn the aileron toward the wind on your takeoff roll can result in very bad things happening......
 
flyingron said:
I still don't know what wind shear has to do with it. Once you've got enough airspeed to get the wheels positively off the ground (and yes in gusty conditions or possible wind shear I hay keep her on the ground longer), it's unclear why you're doing that. Once you're positively off the ground FLY! Keeping the longitudinal access aligned with the runeay does NOTHING to enhance safety.
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CTLSI's comment made me realize that there are times when I deliberately cross my controls on departure and I realized that when the rotors hit our runway the conditions can suddenly exceed my current aircraft's capability. If I am going to be forced back onto the ground due to negative wind shear alignment means a lot. If the take off is uphill and it is gusty it might take me some distance to establish climb. I'm only saying that I don't want a severe crab angle if my departure in the early stages isn't working out.

This condition doesn't happen often and my light sport is more at the mercy than all my prior planes. I think the combination of low stall speed, low drag and light loading is why it will react to gusts so dramatically. I read on the AOPA board that the minimum safe aircraft for our field is a twin turbine.
 
I've never cross controlled an aircraft on take off. I often keep a wing low into the wind on takeoff but as soon as it breaks ground I crab into the wind some, especially in a tail dragger. On landing I often cross control to the max to lose altitude in a taildragger without flaps, often times right down to within a few feet of the runway. To the best of my knowledge , I've never slipped on takeoff. ( over 4000 hours most in taildraggers)
 
Jimmy cooper said:
I've never cross controlled an aircraft on take off. I often keep a wing low into the wind on takeoff but as soon as it breaks ground I crab into the wind some, especially in a tail dragger. On landing I often cross control to the max to lose altitude in a taildragger without flaps, often times right down to within a few feet of the runway. To the best of my knowledge , I've never slipped on takeoff. ( over 4000 hours most in taildraggers)
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Jim,

Your take off technique is what I normally use.

Look at my photo and notice the 13,000' terrain 1 mile from the runway. Also notice the 1,500' high glacial moraines that cause rotors as the winds come down the big canyons, next they go over the runway at a 90 degree angle, hit more high terrain and then rotor back horizontally. That would be the south wind while a west wind collides mid field, maybe even an East wind too.

If all that is happening and I know the wind is going to change dramatically and numerous times crabbing into the wind can be counterproductive if its the next wind you are preparing for.

post-6-0-70905100-1369748077.jpg
 
CTLSi said:
No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
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Lemme see...wind from the right, so right aileron. Wind wants plane to weathervane to the right by pushing on the rudder surface, so I need left rudder. This is going to kill me? Can't count how many times I have done xwind takeoffs without death, injury, or bent metal.

Bob Gardner
 
CTLSi said:
No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
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Wrong!
In a good crosswind I'm cross controlled on most every takeoff. Aileron into the wind and opposite rudder to keep the nose going straight down the runway.

I'll get the tail up as soon as I can which reduces the AOA on the wing and gets it flying sooner, out of the stall AOA regime with the tail down. When the aileron starts working I'll pick up the downwind wing and roll on one tire. Still using rudder to keep it straight with the runway centerline. Cross controlled

If I can't get the wing down into the crosswind, I'll be skipping sideways across the runway waiting for the beast to fly.
 
BillTIZ said:
Wrong!
In a good crosswind I'm cross controlled on most every takeoff. Aileron into the wind and opposite rudder to keep the nose going straight down the runway.

I'll get the tail up as soon as I can which reduces the AOA on the wing and gets it flying sooner, out of the stall AOA regime with the tail down. When the aileron starts working I'll pick up the downwind wing and roll on one tire. Still using rudder to keep it straight with the runway centerline. Cross controlled

If I can't get the wing down into the crosswind, I'll be skipping sideways across the runway waiting for the beast to fly.
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This, when I had about 50 hours, I was a little timid about getting that aileron into the wind, even though my instructor had beat it into my head. Long story short, the wing lifted, the plane weathervaned and I came as close as I ever want to come to a crash while taking off. Never made that mistake again after that.
 
CTLSi said:
No such thing as a slip to ascend, or takeoff. You may crab on takeoff, but if you try to cross control you will stall and crash.
Click to expand...
You might, but most pilots can manage to maintain a slip while climbing without stalling or crashing. Just ask any CFI how well their students do with coordination when taking off early in their training. "More right rudder" is probably the most often phrase that passes through a CFIs lips. :D
 
FTFY... ;)
Jimmy cooper said:
I've never cross controlled an aircraft on take off once the wheels leave the ground. I often keep a wing low into the wind on takeoff but as soon as it breaks ground I crab into the wind some, especially in a tail dragger. On landing I often cross control to the max to lose altitude in a taildragger without flaps, often times right down to within a few feet of the runway. To the best of my knowledge , I've never slipped on takeoff. ( over 4000 hours most in taildraggers)
Click to expand...
 
CharlieTango said:
Jim,

Your take off technique is what I normally use.

Look at my photo and notice the 13,000' terrain 1 mile from the runway. Also notice the 1,500' high glacial moraines that cause rotors as the winds come down the big canyons, next they go over the runway at a 90 degree angle, hit more high terrain and then rotor back horizontally. That would be the south wind while a west wind collides mid field, maybe even an East wind too.

If all that is happening and I know the wind is going to change dramatically and numerous times crabbing into the wind can be counterproductive if its the next wind you are preparing for.

post-6-0-70905100-1369748077.jpg
Click to expand...

I friggen love the Woodstock decal on that tail. Awesome!
 
flyingron said:
I still don't know what wind shear has to do with it. Once you've got enough airspeed to get the wheels positively off the ground (and yes in gusty conditions or possible wind shear I hay keep her on the ground longer), it's unclear why you're doing that. Once you're positively off the ground FLY! Keeping the longitudinal access aligned with the runeay does NOTHING to enhance safety.
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Ron,

My point was that I wanted to remain aligned until my take-off was assured, until a positive rate of climb was established and maintained. You're replies made me question my sanity but the Airplane Flying Handbook says the same thing I was saying.

Airplane Flying Handbook:

As both main wheels leave the runway and ground friction no longer resists drifting, the airplane will be slowly carried sideways with the wind unless adequate drift correction is maintained by the pilot. Therefore, it is important to establish and maintain the proper amount of crosswind correction prior to lift-off by applying aileron pressure toward the wind to keep the upwind wing from rising and applying rudder pressure as needed to prevent weathervaning.

INITIAL CLIMB
If proper crosswind correction is being applied, as soon as the airplane is airborne, it will be sideslipping into the wind sufficiently to counteract the drifting effect of the wind. [Figure 5-5] This sideslipping should be continued until the airplane has a positive rate of climb. At that time, the airplane should be turned into the wind to establish just enough wind correction angle to counteract the wind and then the wings rolled level. Firm and aggressive use of the rudders will be required to keep the airplane headed straight down the runway. The climb with a wind correction angle should be continued to follow a ground track aligned with the runway direction. However, because the force of a crosswind may vary markedly within a few hundred feet of the ground, frequent checks of actual ground track should be made, and the wind correction adjusted as necessary. The remainder of the climb tech- nique is the same used for normal takeoffs and climbs.
 
Nice find! ;)

It's a small matter of technique, but...


...just as in a crosswind landing one may wish to land on the upwind wheel first...

...in a crosswind takeoff I try to have the downwind wheel lift off first.

That way, as I leave the ground I'm already banking into the turn required to establish my wind correction angle.

I don't see why any period of time should be spent in a slipping climb.
 
I normally do a barrel roll just after takeoff. It's worked every time.
 
FastEddieB said:
I don't see why any period of time should be spent in a slipping climb.
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The Airplane Flying Handbook advocates it for the same reason I do. This sideslipping should be continued until the airplane has a positive rate of climb.

Our light sports normally leap into the air and establish a positive rate of climb immediately so this is not normally an issue. Flying my light sport from Mammoth Yosemite gives me the opportunity to depart in conditions where achieving a positive rate of climb isn't a given. If the shear forces me back into contact with the runway or if the shear causes me to abort the take-off I prefer to be aligned and over the runway if not the center line.

With a laminar flow crosswind or even a low altitude take-off I use a crab right away.
 
If you get into ground effect and you sit there slipping for some ridiucious reason you might NEVER get a positive rate of climb. Slipping is inefficient. Do that at a high DA airport in an underpowered airplane and you'll meet your maker.

Once the wheels come off the ground there is ABSOLUTELY NO REASON to continue to slip. Ditch the slip and fly coordinated so that you can actually, you know, fly away.
 
jesse said:
If you get into ground effect and you sit there slipping for some ridiucious reason you might NEVER get a positive rate of climb. Slipping is inefficient. Do that at a high DA airport in an underpowered airplane and you'll meet your maker.

Once the wheels come off the ground there is ABSOLUTELY NO REASON to continue to slip. Ditch the slip and fly coordinated so that you can actually, you know, fly away.
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Jesse,

Why do you think the FAA included "This sideslipping should be continued until the airplane has a positive rate of climb." if its going to cause me to meet my maker? I have been flying very light planes out of Mammoth since the 80s and learned this lesson decades ago. Our DA is usually about 10,000'
 
CharlieTango said:
Jesse,

Why do you think the FAA included "This sideslipping should be continued until the airplane has a positive rate of climb." if its going to cause me to meet my maker? I have been flying very light planes out of Mammoth since the 80s and learned this lesson decades ago. Our DA is usually about 10,000'
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Depending on how close to the edge you are, you may never establish a positive rate of climb while in a slip, a slip is aerodynamically inefficient, slips are often used to LOSE altitude because of that feature. If you want to go UP you do NOT want to be slipping.

If you're about to sink back down to the runway then yes you may want to go back into the slip to realign your wheels and prevent sideload before you hit the runway. But if you're sitting there in ground effect a slip is HOLDING YOU BACK from the climb you would have without it.
 
I would think that if you're so close to the performance limits that you can't get out of ground effect in a crosswind slip, you may have a bit of trouble with even light winds around all that terrain.

And God help you of you fly over Lake Crowley. The sink will get you.

I think the real issue is that people dramatically underestimate the capabilities of the aircraft. Do you have any idea how many people have told me that a 172 has no chance at Tahoe? Except it does. Even a 160 HP can handle the density altitude there on a 90 deg day loaded to max gross. Now, winds can be a significant factor, so that's not a good zone to be in, but the DA will work fine as long as you don't do something stupid like try to take off full rich or try to yank the yoke until you get 500 FPM.

I still get funny looks when I tell people I did my mountain checkout in a Warrior at Big Bear. Yes, I was looking for ridge lift anywhere I could get it, and had to be very aware of winds. But it wasn't anywhere near as scary as some people make it out to be.
 
jesse said:
Depending on how close to the edge you are, you may never establish a positive rate of climb while in a slip...
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That's not how it happens, I climb at ~700'/min and get off in 5 seconds. I don't sit in ground effect, instead i lower the nose and accelerate to Vy, my CT wants to climb. The problem is staying airborne when negative shear is encountered while still close to the ground.

I realize that slipping degrades performance and I minimize it.

Why do you think the FAA advises the slip prior to establishing a positive rate of climb if it is such bad advice?
 
CharlieTango said:
That's not how it happens, I climb at ~700'/min and get off in 5 seconds. I don't sit in ground effect, instead i lower the nose and accelerate to Vy, my CT wants to climb. The problem is staying airborne when negative shear is encountered while still close to the ground.

I realize that slipping degrades performance and I minimize it.

Why do you think the FAA advises the slip prior to establishing a positive rate of climb if it is such bad advice?
Click to expand...

I've explained my reasoning above, just because you don't like it, doesn't mean I'll change it if asked again :)

It sounds like you aren't at the margin of your performance but when you are at the margin sitting there in a slip trying to climb makes about as much sense as landing 20 knots too fast into a short strip.
 
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