Slipped takeoff

[CharlieTango]

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.

I understand your reasoning and like it just fine. You are in agreement with most others as well. I wasn't asking you to repeat it just to comment on why the FAA isn't on the same page.

Fast Eddie dug up the quote and posted it and even he argues against it.

I'm only at the margin when the winds are colliding and rotoring and tail-winding me.

 

[CharlieTango]

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.

I fly over Crowley Lake all the time, I like to look at the pelicans.

I used to have a 180hp Skyhawk and 180hp Cherokee, the 160hp versions can be poor climbers. It was in my Skyhawk that I first learned that take-offs here are not always assured even if you get airborne in a normal distance.

 

[MAKG1]

I was being facetious.

Flying around so close to performance limits close to the ground that a takeoff slip matters would have all kinds of perils from very small effects that would otherwise not be a concern, and I'd really rather abort the takeoff.

But we don't really fly THAT close. At least not without a tow plane….

A 160 HP 172 isn't comfortable at that kind of DA, so it's really important to have an abort point well out of ground effect and enough runway to land ahead of it if you don't like it. Sinking air over the runway is not pleasant. The 180 HP conversions (as opposed to the ones that came with 180 HP) are substantially more capable. The SPs are heavy, in proportion.

 

[flyingron]

I'll agree with the Positive Rate qualification. Much the same as raising the gear.

 

[Jaybird180]

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.

Jesse,

Do you realize the discussion is about using a side-slip during a crosswind takeoff (which BTW is a coordinated maneuver - it's all about relative wind, not relative runway when the wheels leave the ground) not a forward slip (maneuver used to turn the side of the aircraft to the relative wind to increase drag).

Not being a smartass, but does this now change your answer?

 

[RoscoeT]

Jesse,

Do you realize the discussion is about using a side-slip during a crosswind takeoff (which BTW is a coordinated maneuver - it's all about relative wind, not relative runway when the wheels leave the ground) not a forward slip (maneuver used to turn the side of the aircraft to the relative wind to increase drag).

Not being a smartass, but does this now change your answer?

First, I don't think you need to try to educate Jesse on what a slip is or isn't. Second, you're furthering this side-slip vs. forward slip NONSENSE. Third, I'm not sure you understand slips in the first place since there is NO slip that is coordinated - if by 'coordinated' you mean ball in center. Why do we make such simple things so difficult?

 

[FastEddieB]

Fast Eddie dug up the quote and posted it and even he argues against it.

Let me qualify that...

In the vast majority of my takeoffs, a positive rate of climb is virtually assured as the wheels leave the ground. Hence, my turn into the wind begins at that point.

If I was struggling along in ground effect and committed to taking off, I would still likely crab for more performance.

I think slipping would only be required in that (usually) short transitional period when the plane might actually sink back onto the runway, and you would want to be aligned with the runway if that happened. Even then, I think most of us could "kick it straight" pretty quickly to avoid landing in a crab and the side loads that would entail, if we saw ground contact inevitable.

Overall, I think we're debating a "fringe" topic that is hardly ever a factor.

Or maybe not - my airport elevation is not that high.

 

[Greg Bockelman]

Jesse,

Do you realize the discussion is about using a side-slip during a crosswind takeoff (which BTW is a coordinated maneuver - it's all about relative wind, not relative runway when the wheels leave the ground) not a forward slip (maneuver used to turn the side of the aircraft to the relative wind to increase drag).

Not being a smartass, but does this now change your answer?

Hmm. A slip is a slip is a slip. Side slip, forward slip, the execution is the same. And by definition a slip is an UN-coordinated maneuver. Bank one way, opposite rudder.

As far as when to transition out of the slip, one must take care not to do that until a positive rate of climb is established. You don't want to remove the slip and then settle back onto the runway. That would be bad, especially in a tailwheel airplane.

 

[Jaybird180]

Hmm. A slip is a slip is a slip. Side slip, forward slip, the execution is the same. And by definition a slip is an UN-coordinated maneuver. Bank one way, opposite rudder.

As far as when to transition out of the slip, one must take care not to do that until a positive rate of climb is established. You don't want to remove the slip and then settle back onto the runway. That would be bad, especially in a tailwheel airplane.

remove the slip = settle back to the runway - sure sounds like a loss of performance to me.

 

[Jaybird180]

First, I don't think you need to try to educate Jesse on what a slip is or isn't. Second, you're furthering this side-slip vs. forward slip NONSENSE. Third, I'm not sure you understand slips in the first place since there is NO slip that is coordinated - if by 'coordinated' you mean ball in center. Why do we make such simple things so difficult?

By my explanation, it should be obvious that the position of the ball is irrelevant, only thing I was addressing is relative wind.

 

[RoscoeT]

By my explanation, it should be obvious that the position of the ball is irrelevant, only thing I was addressing is relative wind.

I'm still unclear what you think we don't understand about slips. You said a slip is a coordinated maneuver. What's your definition of coordinated? Your posts are very inarticulate. This means they don't make much sense.

 

[flyingron]

By my explanation, it should be obvious that the position of the ball is irrelevant, only thing I was addressing is relative wind.

Eh? The relative wind is going to be primarily the same as the ball. The definition of coordinated flight is that the relative wind is aligned with the longitudinal axis of the plane. The ball is just another way of visualizing this (if the FAA didn't insist on a nonsensical definition of coordinated in their private pilot pablum, this wouldn't be so confusing, in my opinio).

A slip (forward or side) is by definition UNCOORDINATED. It's forcing the longitudinal access out of alignment with the relative wind.

A better way of visualizing it than the ball if you don't have a big turbulant fan in front of the windshiled is a "yaw string." You hang a piece of yarn like a little penant in front of the pilot. If the wind is blowing it straight back at you, you're coordinated, if it is blowing to the right or left, you're not.

 

[jesse]

remove the slip = settle back to the runway - sure sounds like a loss of performance to me.

Removing the slip will make it less likely you'll settle back to the runway. I do a fair amount of tailwheel flying in a fairly underpowered airplane. When I get the wheels off the runway I coordinate the airplane so I can start my very slow climb.

Yes if for some reason you find that you're about to hit the runway again you might have to go back into the slip, but you messed up or something really interesting happened to cause that. It's a non-issue and easy to correct if you discover you're about to touch down again.

There is absolutely no such thing as a coordinated slip. It does not exist.

 

[RoscoeT]

remove the slip = settle back to the runway - sure sounds like a loss of performance to me.

Greg was NOT saying that removing the slip will cause settling back to the runway. If you think it will, then you are having some real issues grasping aerodynamics.

 

[Jaybird180]

If I wanted hostility in an internet forum, I'd go to the spin zone.

Got it on the ball = wind direction explanation.

 

[RoscoeT]

If I wanted hostility in an internet forum, I'd go to the spin zone.

Got it on the ball = wind direction explanation.

Sorry for the hostility, but we still don't have a clue what you're trying to say.

 

[VanDy]

this guy does

 

[PaulS]

I was taught aileron into the wind, rudder to keep aligned with the runway as necessary. If wind is strong enough that the down wind wing lifts before the other wheel, then that is just the way it is. As soon as you are flying, crab into the wind and get ball centered for climb. If you allow the upwind wheel to lift first from a crosswind you could end up in a world of hurt.....