Jump to content

Slip on final


Recommended Posts

Hopefully on final you're fully configured, so with no more drag to hang out there that seems like your only option - except a go-around. I've found in my C that I can accelerate as I "dive" to about 200-300', in VMC only, and scrub the speed on short final, always ready for another 0.2 hours if needed. A buddy mentioned for the 3,000 to 500' regime using the J-bar as a speedbrake - about 3 or 4 inches of travel is all it takes to get a good change in airframe drag. Haven't tried it - has anyone else? Just curious.

Patrick

Link to comment
Share on other sites

Not recommended for Long Bodies...

Something about shadowing the tail causing a tail stall.

Fortunately, this does not apply for mid and short bodies.

LBs get speed brakes to enhance altitude/speed/energy control.

Keep the nose pointed downish while slipping...

Best regards,

-a-

Link to comment
Share on other sites

Not recommended for Long Bodies...

Something about shadowing the tail causing a tail stall.

Fortunately, this does not apply for mid and short bodies.

LBs get speed brakes to enhance altitude/speed/energy control.

Keep the nose pointed downish while slipping...

Best regards,

-a-

 

+1 on this one.  Slips are easy in my E model, but I recall about five years ago we lost a long body with an very experienced Mooney driver and instructor because of something similar on final.

 

Apparently not a good idea for the long bodies.

Link to comment
Share on other sites

That was a blast from the past. I didn't realize I had started that first thread. Not sure whether I'm glad or lucky that I hadn't reviewed this in awhile. I went through a three month period early this year where my speed brakes were inop, and I was happily slipping my long-body down out of altitude and to reduce speed for final. However, I don't recall ever using the slip ON final, so I was probably not in any danger. And I can tell you that even after prolonged slips I don't recall ever feeling like the plane was losing control...probably because I was still well above danger speeds.

 

Thanks for the reminder!

Link to comment
Share on other sites

The Bo has a similar restriction on slipping with a certain amount of fuel in the tank. Also, the POH says not to take off with less than 9 gal (?) in one tank.

 

I don't know why, by the Bo slipped well and this was a comfortable strategy to deal with a crosswind. But with both my F and R, the crab and kick method works very well for me. I don't use the slip on final to bleed off speed. For normal every day landings, I am not trying to make the 1st turn off. I target smooth touch downs and whatever length it uses, that is what is uses. Passengers appreciate this and so do my brakes and tires. As most RR I use are 5000ft plus, it is not a problem. 

 

Even if the slip is not a recommended procedure for final approach for long bodies, I think we should still practice the slip (at altitude) for emergency procedures. That skill may be needed one day to put down in a short field in an emergency. 

Link to comment
Share on other sites

I can forward slip my 231 all day at 85kts., and that is a pretty good approach speed.  The 231 is not a "long body" but it is in the group of Mooney for which slips have been controversial.  The trick is to keep the speed up.

 

It is not much of an issue for me though.  I have time in both the 231 and the J, and the 231 feels like a heavier aircraft.  If you bring the engine in the 231 to idle on the final approach, sooner or later you are going to need to bring the nose up to keep on a reasonable glide slope, and the minute you do that any excess speed comes off quickly.  Invariably, you will wind up putting in some power just before the fence in order to keep both the glideslope and the airspeed where they should be.  The J, on the other hand, did not react in the same way.  It seemed quite a lot lighter and, even with gear extended and engine at idle would decline to slow down if you started the final approach with a bit too much speed.

Link to comment
Share on other sites

The Bo has a similar restriction on slipping with a certain amount of fuel in the tank. Also, the POH says not to take off with less than 9 gal (?) in one tank.

 

 

There are others also. It's not an uncommon restriction or recommendation in low-wing aircraft. As another example, the Cirrus manual mentions it in two places. In both, it's a recommendation, not a limitation.

 

I haven't seen every version, but seems to me that it's typically a recommendation not a restriction or limitation, like the famous "avoid slips with flaps" Cessna is famous for. The reasons seem to vary, but it usually has something to do with fuel, either an interference with flow or venting.

 

Thank goodness it doesn't mean "no slips allowed." A prohibition on crosswind landings would kind of dampen the usefulness of an airplane.

Link to comment
Share on other sites

If you are at 1.2 Vso on final you don't have a lot of room to slip, all airplanes slip, and are constantly slipping. Small slips are great way to adjust glide path, barn door slips require airspeed, unloading the slip gently will decrease any buffet until you find that sweet spot. Never push the slip past the point of positive control in all axis. Slips are part of aviation, like breathing is to humans, part of proficiency is learning to properly adjust glide path with suttle slips etc. Heavy slips like a Maule @50 mph w 40 deg of flaps and a boot full of rudder to sneak it in a tight pasture are not for Mooney's, but controlled slips to adjust glide path are perfectly ok in any airplane. Exaggerated slips close to 1.2 Vso are asking for trouble unless highly proficient and conditions are adequate. Gusty winds in wrong direction can get your attention. But answering the first question, in this thread,a slip is and should be an arrow in the quiver of any pilot in any airplane. Obviously abide by POH restrictions and slip away... Just thought I would share some professional knowledge.

Link to comment
Share on other sites

+1 on loading and speeds. Slips are effective and safe if, like anything else, done within the envelope. Practice them AT ALTITUDE and add them to your toolkit.

Before l became a Mooney owner almost two decades ago, I heard all of the Mooney horror stories: hard to land, easy to bounce, too slick, too small, blah blah blah. Fortunately I had heard the same things about my primary trainer and first plane, the Grumman AA1B, and had stick time in another plane with an awful rep, the Comanche.

Far too many of us Mooney pilots have never landed or taken off without flaps, fly final at 90 knots because "my airplane doesn't like to fly slower," or drop the yoke as soon as the mains touch. Get out there and learn the aircraft. If you want some company, there are experienced Mooney CFIs like Don Kaye who will help. Don't let the "old wives" discourage you.

  • Like 2
Link to comment
Share on other sites

Very well put,

 

Those old wives tales and urban legends are a plethora of misinformation.

 

ie, The person flailing uncontrollable on the ground was not possessed by the devil after all, but was found later, through scientific discovery, to have had epilepsy.

 

That being said???

 

Best,

 

DH

Link to comment
Share on other sites

  • 3 weeks later...

If you want to descend quickly, in a short distance, why not...?

Gear down (@140KIAS), speed brakes out, speed back to 160 KIAS.

Descent rate is huge, while being comfortable (sort of).

Speed brakes and gear increase their resistance greatly with speed.

Gear restriction in the R is 160KIAS for being extended, 140 KIAS for operation. (Probably same for all LBs)

Essentially, the restriction being discussed is don't slip the LB near the ground where a stall/spin is irrecoverable.

Slow speed near the ground is definitely more of a cross control challenge.

Your thoughts are greatly appreciated,

-a-

Link to comment
Share on other sites

  • 2 weeks later...

SO still being new in type, sometimes I find myself high on final, I don't want to gain airspeed and watch the airport go by my window, I find a slip works beautifully and the airplane slips really nicely and maintains the desired stabilized approach and spot on my airspeed.

 

Wish my gear speed was 160.

 

I'm a medium body, not a long, but I have speed brakes. I don't find they do much at pattern speeds.

Link to comment
Share on other sites

Consider the smoothness of the transition into and out of the slip.

Consider what happens if you let your foot slip off the pedal and dump the rudder input in a snappy motion...

Better to learn some things by talking about them, than by experience.

I'm just a PP, not a CFI

Best regards,

-a-

Link to comment
Share on other sites

Consider the smoothness of the transition into and out of the slip.

Consider what happens if you let your foot slip off the pedal and dump the rudder input in a snappy motion...

Better to learn some things by talking about them, than by experience.

I'm just a PP, not a CFI

Best regards,

-a-

Personally as narrow as the foot box is on our 231 I don't know if my foot CAN slip off the rudder, but any extra rolling would be pretty hard to miss and not correct immediately.

I find the transition in and out to be quite smooth, as I find most things in the mooney (except my landings :angry: )

 

I like the discussion though, just because it's worked in the past doesn't mean it's necessarily a good, or bad, idea.

Link to comment
Share on other sites

The take off and slip restrictions on the Bonanza have to do with unporting the fuel system , If you have ever been close up to a V tail it is HUGE , I don't even know if it is possible to shadow it enough to stall it.... Also the Mooneys have a very narrow airfoil on the tails , which may contribute to the possibility of stalling the tail in a slip.......Just an observation , no real engineering data to back it up....

  • Like 1
Link to comment
Share on other sites

PV,

I may have been the only one to drop the rudder input in my C...

Being young and flying below maneuvering speed I thought it may be a normal practice.

The tail would snap back to center and oscillate as the frequency would diminish.

Looking back on that, I think I may have missed something important...

Best regards,

-a-

Link to comment
Share on other sites

If I remember, the no slip caution applies to long bodies at slow speeds, where the wing can shadow the tail and cause a tail stall. My C slips very well, but I've never been the kind to think, I'm high, let's slip, then put my foot to the floor. I make coordinated input of rudder and aileron (resulting in uncoordinated flight), increasing both until I am satisfied with the result. I remove them similarly but quicker, then establish the correct crab angle. There's no need to be harsh or jerky, and it also. Inimizes trouble with fuel ports when you're low at the end of a trip.

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.