Engine Failure During Slip

[vdehart]

Half fuel on the low wing and a light slip to landing towards the low wing. Slipping for about ten seconds, fifteen max, when the engine quits on me. I quickly switch to the high tank but the priority becomes dead sticking her down onto the runway. Got her in safe. POH states to avoid prolonged slipping towards a near empty tank. I've slipped this plane a thousand times in the same way with the same amount of fuel and never experienced a failure. I wouldn't consider half a tank "near empty".

The hard and fast rule now in any airplane is going to be to keep the selector on the high wing. Big big lesson learned!

 

[docmirror]

Thank goodness for sphincters.

 

[Subsea]

Thank goodness for sphincters.

I've got an upholstery guy that can repair that little hole in the seat.

 

[vdehart]

Honestly, I'm patting myself on the back for flying the s**t out of the plane right down to the runway. But seriously, this was a topic I never fully appreciated. There is no reason to take this risk if you have the selector.

 

[txflyer]

Glad you're o.k.!

 

[frfly172]

I guess the POH does serve a purpose. Glad it worked out for you.

 

[scooter]

What type of plane?

 

[Zeldman]

Since your slipping the plane, that means you are high so no reason to miss the runway.

Glad you got on the ground safely. Lesson learned.

 

[Henning]

Yeah, I don't typically use slips for multiple reasons, this included. If I'm high on final I typically pull the throttle and pull the nose up to chirp the stall horn and just let it sink nose high and coordinated. I get a pretty good sink rate, and the non pilot passengers don't go through the discomfort of a slip (most don't like it one bit).

 

[wilkersk]

Yeah, I don't typically use slips for multiple reasons, this included. If I'm high on final I typically pull the throttle and pull the nose up to chirp the stall horn and just let it sink nose high and coordinated. I get a pretty good sink rate, and the non pilot passengers don't go through the discomfort of a slip (most don't like it one bit).

I'm curious; how high of a sink rate do you get doing that?

 

[azure]

Yeah, I don't typically use slips for multiple reasons, this included. If I'm high on final I typically pull the throttle and pull the nose up to chirp the stall horn and just let it sink nose high and coordinated. I get a pretty good sink rate, and the non pilot passengers don't go through the discomfort of a slip (most don't like it one bit).

Would you do that on short final though? I wouldn't if the wind was the slightest bit gusty.

 

[Henning]

Would you do that on short final though? I wouldn't if the wind was the slightest bit gusty.

By short final I'm where I need to be or go around.

 

[Henning]

I'm curious; how high of a sink rate do you get doing that?

It depends on the plane, I'm not looking at panel, I'm looking out the window, but the threshold moves up in the windscreen rather quickly and I can get the nose back down.

 

[MAKG1]

If this is a low wing, doesn't the POH checklist say to switch to the fullest tank?

If it's a Cessna, you need to have your fuel system looked at, as it should be impossible to unport both tanks unless one is empty. And your "hard and fast rule" doesn't work here, as the selector must be on BOTH for takeoff and landing.

 

[Bill Watson]

Yeah, I don't typically use slips for multiple reasons, this included. If I'm high on final I typically pull the throttle and pull the nose up to chirp the stall horn and just let it sink nose high and coordinated. I get a pretty good sink rate, and the non pilot passengers don't go through the discomfort of a slip (most don't like it one bit).

A lot depends on the plane.

In my Maule, a slip was a good way to steepen the approach on a 'STOL' plane that can be challenging to get a good steep approach path out of. And slips are very effective. And it's a high wing. And slowing to increase the angle or sink isn't very effective, and slowing created some risks, mainly that you become engine dependent for the roundout or an unexpected wind change or the expected wind gradient.

In my RV10, slips just aren't that effective. But it has a really sweet response to power during the descent.

However, in general, once I pick and approach speed relative to weight and conditions, I'd be loathe slow below that in order to increase sink or angle. You start giving up energy management margins which can only be corrected with power. Wind gradient or unexpected wind changes can suddenly make your safe and sound landing engine dependent on engine power.... why do that?

Depends on the plane though... I found that a Mooney I flew had a speed where the descent rate would increase significantly. I'm sure it was tied to a shift in laminar flow on the wing. Normal approaches would typically be done just above that speed but just below that speed was a safe as well, say 1.2 Vs, but was very effective in making everything steeper and shorter.

Depends on the plane

 

[Henning]

A lot depends on the plane.

In my Maule, a slip was a good way to steepen the approach on a 'STOL' plane that can be challenging to get a good steep approach path out of. And slips are very effective. And it's a high wing. And slowing to increase the angle or sink isn't very effective, and slowing created some risks, mainly that you become engine dependent for the roundout or an unexpected wind change or the expected wind gradient.

In my RV10, slips just aren't that effective. But it has a really sweet response to power during the descent.

However, in general, once I pick and approach speed relative to weight and conditions, I'd be loathe slow below that in order to increase sink or angle. You start giving up energy management margins which can only be corrected with power. Wind gradient or unexpected wind changes can suddenly make your safe and sound landing engine dependent on engine power.... why do that?

Depends on the plane though... I found that a Mooney I flew had a speed where the descent rate would increase significantly. I'm sure it was tied to a shift in laminar flow on the wing. Normal approaches would typically be done just above that speed but just below that speed was a safe as well, say 1.2 Vs, but was very effective in making everything steeper and shorter.

Depends on the plane

You give up energy either way, that's the whole point of either. Granted, STOL makes slowing less effective.

 

[luvflyin]

[QUOTE=vdehart;1818070......I've slipped this plane a thousand times in the same way with the same amount of fuel and never experienced a failure. I wouldn't consider half a tank "near empty".

The hard and fast rule now in any airplane is going to be to keep the selector on the high wing. Big big lesson learned![/QUOTE

I'd be looking into what to caused the failure. If you you've slipped it a thousand times before, the same way, same fuel, no problems, there just might be big problem with the airplane. If your doing forward slips to lose altitude how about keeping the selector on the fullest tank where it belongs and slip it in the direction that keeps that tank high side. A side slip for crosswind landings shouldn't be a problem because you aren't in that for more than a few seconds and the degree of slip isn't that great. Anyway, you need to find out why the engine quit. The slip causing it doesn't add up if you've done it a thousand times before without a problem

 

[Stewartb]

I'm curios about the airplane type in the OP.

STOL airplanes and pilots dominate around here. Nobody I know or have observed slips an airplane that's equipped with flaps.

 

[Henning]

I'm curios about the airplane type in the OP.

STOL airplanes and pilots dominate around here. Nobody I know or have observed slips an airplane that's equipped with flaps.

That's because they don't get themselves into a situation that needs it. (except crosswinds, but that's a different deal, not an energy management correction)

 

[Cap'n Jack]

I'm curios about the airplane type in the OP.

STOL airplanes and pilots dominate around here. Nobody I know or have observed slips an airplane that's equipped with flaps.

I don't use slips as much here, but I used them a lot in New Jersey with C-150, C-152, and C-172. I would landing be landing into a head wind that diminished down low, which would leave me high but not fast. If I knew it was there, I could adjust earlier in final approach, but if I didn't know about it, I would just slip it down, even with full flaps.

I got a better sense of wind shear when I was working on an IFR certificate keeping needles centered.

 

[LDJones]

I was towing gliders Wednesday and was slipping the heck out of the SuperCub to get down after release. At one point I got a stumble out of the engine which prompted me to switch tanks!

 

[Capt. Geoffrey Thorpe]

If this is a low wing, doesn't the POH checklist say to switch to the fullest tank?

If it's a Cessna, you need to have your fuel system looked at, as it should be impossible to unport both tanks unless one is empty. And your "hard and fast rule" doesn't work here, as the selector must be on BOTH for takeoff and landing.

I don't recall having a "both" setting in the Cessna I used to fly. But I do know you could unport the low tank and make a reduction in the engine noise.

 

[Bill Watson]

You give up energy either way, that's the whole point of either. Granted, STOL makes slowing less effective.

Yes, or perhaps No. There's a significant difference.

Remove the engine from the exercise and you'll find that slipping is similar to spoiler use. That is, you both operations add drag (and don't add lift) to increase sink rate and angle but the drag can be removed instantaneously without further energy penalty.

Pitching up and slowing down is comparable to applying flaps - you are now in a lower energy configuration that can not be recovered from without a significant exchange of altitude (or application of power which is the power dependent part).

 

[Bill Watson]

I'm curios about the airplane type in the OP.

STOL airplanes and pilots dominate around here. Nobody I know or have observed slips an airplane that's equipped with flaps.

I did in my old Maule. I certainly did in various Cessnas which slip with flaps quite nicely notwithstanding airspeed and elevator blanking issues.

Effective flaps sort of negate the absolute need for slips. Maule flaps are remarkably ineffective when compared to the excellent flaps on Cessnas but both families of aircraft slip nicely. My RV10 slips but it's just not that useful.

I think ol' Gordon Baxter wrote up the joys of slipping a 182 in one of his Bax Seats. He was flying someone else's 182 with the owner aboard. He was a bit high and setup a deep slip with power on a curving final. The way he described the joy of having all the controls hard over and pulled into his gut with the runway threshold square in the crosshairs, carrying just the right amount of power was sweet. But all ruined when the owner declared "my plane" and pulled all of the sweetness out to land somewhere further down the runway.

It would be interesting to record such a landing on a PFD with a FPM (Flight Path Marker). The horizon all askew and the runway slanted over but with the FPM dead on the numbers. Of course you shouldn't be looking if you are flying it! Nope.

 

[Stewartb]

Whatever works for you. If I need to slip to lose altitude I'd be trying to fix a screw-up. That's better resolved by doing a lap and setting up a more appropriate approach. I use steep approaches and full flaps to a narrow short strip that's known for squirrelly winds and mechanical turbulence all the time. No slips necessary.

 

[Henning]

Yes, or perhaps No. There's a significant difference.

Remove the engine from the exercise and you'll find that slipping is similar to spoiler use. That is, you both operations add drag (and don't add lift) to increase sink rate and angle but the drag can be removed instantaneously without further energy penalty.

Pitching up and slowing down is comparable to applying flaps - you are now in a lower energy configuration that can not be recovered from without a significant exchange of altitude (or application of power which is the power dependent part).

True, but as I said if I'm low enough for that to matter, it's time to go around.

 

[Witmo]

Whatever works for you. If I need to slip to lose altitude I'd be trying to fix a screw-up. That's better resolved by doing a lap and setting up a more appropriate approach. I use steep approaches and full flaps to a narrow short strip that's known for squirrelly winds and mechanical turbulence all the time. No slips necessary.

To each his own. In order to accomplish the steepest approach to the shortest landing, full flaps and a steep slip are necessary. Do you need to slip to perform a normal approach? --no. Do you need to slip to do a maximum performance landing, yes. Anything less is less than maximum. I often slip on landings and if I were to lose the engine for whatever reason, it's not that big a deal as the landing is already assured--I'd just end up a little further down the runway before touching down. I wouldn't be slipping if I couldn't reach the runway without power. I do see pilots salvage too high an approach by adding a slip into the equation. It's just another tool to use and it takes practice to use it effectively. If you go around every time you're slightly high on the approach rather than add in a slip, that's your choice. Going around after a real loss of an engine because you were too high going into that obstructed clearing won't be an option. In that case you might wish to have practiced using a slip to get down.

 

[Dan Thomas]

I'd be looking into what to caused the failure. If you you've slipped it a thousand times before, the same way, same fuel, no problems, there just might be big problem with the airplane.

Naw, he's just been close to unporting before and didn't know it. If the engine was running fine on that tank before the slip, the system is fine. He just had a little less fuel than before, or slipped a little more aggressively than before, or both. The outlet ports don't have any tendency to move up, but the fuel gauges do have a tendency to lie to the pilot.



Dan

 

[CT4ME]

At least some models of Cessna 210 are placarded with “Avoid landing approaches in red arc and over 30 second slips under 1/2 tank.” I was amazed at the Half Tank aspect.

 

[zaitcev]

Yeah, I don't typically use slips for multiple reasons, this included. If I'm high on final I typically pull the throttle and pull the nose up to chirp the stall horn and just let it sink nose high and coordinated.

Every time Henning drags out that idea, I have to reply with the following quote from Denker:

"Looking at figure 7.9, you may suspect that you can increase the angle of descent by flying at speeds well below VL/D. In principle, this is possible — but such a procedure is even more unwise and unprofessional than the high-speed procedure discussed in the previous section.

The main problem is that by the time you achieve a significant increase in descent angle, your airspeed will be much too close to the stall. A slight gust, windshear, or imperfection in pilot technique could cause a stall. Remember, stalling on approach is the #1 way to cause a fatal accident.

A secondary problem with such a procedure is that it probably involves such a nose-high pitch attitude that you can’t see where you are going. A third problem is that you might not have enough energy to flare; if you try to raise the nose too quickly it will just cause an accelerated stall.

It is possible to construct scenarios (such as landing on a very short runway with an obstructed approach) where a steep descent on the back side of the power curve is the only way to get the job done. However, before attempting such a task, you should make sure you have the appropriate specialized training and practice. In most cases it is wiser to just choose a different place to land."

(by http://www.av8n.com/how/htm/power.html#sec-backside-descent)

I've done slowing below Vy many times myself, but only a little bit, not down to "chirping". Usually that is enough. If it's not, either slip, go hard on flaps, or go around.

 

[FastEddieB]

I use full flaps almost all the time in my Sky Arrow, and did so in my Cirrus.

If I err on the approach, I try to do it on the high side, so I use small to medium slips routinely to "fine tune" my landing spot, even with full flaps. Got fairly good with slips when I owned a Citabria without flaps.

Works well for me - others can do whatever they want.

And if anyone recommended slowing down to near the stall to increase sink rate, I'd say that's very bad advice, for reasons already pointed out and which seem obvious.

 

[Stewartb]

Heaven forbid you might hear a stall horn chirp during a high performance short landing!!!!

 

[FastEddieB]

Heaven forbid you might hear a stall horn chirp during a high performance short landing!!!!

Mine goes off all the time. But it's way pessimistic.

I'll hold that anything less than 1.2 Vso leaves previous little room for error.

Not saying a bush pilot might not get comfortable nibbling at that edge of the envelope on final. Seen it at Valdez (on video). But would warn against it for most pilots most of the time.

 

[Stewartb]

Most of the Valdez guys are dragging in with power. Hanging on the prop. Watch STOL guru Paul Claus operate his own planes. His approaches are a lesson in managing power, altitude, and airspeed to result in safe and reliable very short landings in real world conditions.

The past couple of years have been dominated by slatted wings. Those are a different animal.

 

[Witmo]

Most of the Valdez guys are dragging in with power. Hanging on the prop. Watch STOL guru Paul Claus operate his own planes. His approaches are a lesson in managing power, altitude, and airspeed to result in safe and reliable very short landings in real world conditions.

The past couple of years have been dominated by slatted wings. Those are a different animal.

While I practice power off approaches frequently, I don't practice unobstructed short field landings using power and hanging on the prop. Lose an engine on one of those and you'll never make the runway. I cringe every time I see someone dragging it in from a bomber size pattern. Okay, it' not the same as the Valdez guys, but an engine failure will have the same result.

 

[vintage cessna]

While I practice power off approaches frequently, I don't practice unobstructed short field landings using power and hanging on the prop. Lose an engine on one of those and you'll never make the runway. I cringe every time I see someone dragging it in from a bomber size pattern. Okay, it' not the same as the Valdez guys, but an engine failure will have the same result.

Are you also selective about what airports you depart from? An engine failure at many airports on takeoff will leave you in deep doo doo.

 

[brian]]

Still have most my time in a DA20 - that is one aircraft essentially built for slipping One gas tank (no unporting issues) and a slippery aircraft setup of a lot of good training.

The POH for the -35 say no more than 30 seconds of slip. Some say that the new bladders omit this issue, but with all the drag from the flaps, I just haven't had a need to slip.

 

[Fearless Tower]

Who slips for more than 30 seconds???

 

[Henning]

Who slips for more than 30 seconds???

Twin drivers OEI is about the only scenario I see.

 

[txflyer]

I don't like slipping the wagon with full flaps. The sink rate is down right scary and it's weird feeling... like unstable.

I've only slipped it a few times just for fun. With the barn door flaps I never need to in the real world.

Just slow down and put the angle of the wing to the ground like you're in a climb and she'll come right on down. You make it to your touchdown point with power.