Video~Crash into cornfield by CT Monroe Michigan

designrs · Post by **designrs** » Sun Aug 26, 2012 5:51 pm

Thanks Paul. I will keep that in mind and study it both on simulator and in aircraft.

After reviewing the video link above I don't see how that would apply as the objects are clearly below the aircraft and no longer in the windshield, yet the aircraft is loosing altitude as it passes over the obstacle. In the video it looks like the plane will clear it.

Example situation:
Small airport. Short field. No VASI. Aircraft needs to pass over trees on approach. Flaps are at max. Power off. Lightsport still glides quite well. You really rather not slip. So you'd like to pass over those trees as low as safely possible. The pilot does not have a lot of experience so any obstruction feels close unless the plane is waaaay over it.

Suggestions for the pilot for judging safe passage over trees?

What is considered to be a safe clearance?

drseti · Post by **drseti** » Sun Aug 26, 2012 5:54 pm

designrs wrote:What is considered to be a safe clearance?

It's a matter of personal preference, of course, but I always like to be no less than a full wingspan above any obstacle on the final approach path. (More if it's turbulent, gusty, or otherwise in any conditions that will compromise my consistent glidepath.)

designrs · Post by **designrs** » Sun Aug 26, 2012 5:58 pm

OK now I see it... applying the wingspan rule that aircraft was way too low!

I keep re-watching the video seconds before it clipped the wire. It's an informative visual study. According to your reference the pilot needed at least ONE MORE wingspan of altitude.

Thanks!

designrs · Post by **designrs** » Sun Aug 26, 2012 6:07 pm

I guess an important part of that equation is to be at least a wingspan above the obstacle AS THE PLANE PASSES OVER such obstacle. So it had better LOOK AND ACTUALLY BE HIGHER than one wing span while approaching the obstacle in consideration of a high sink rate landing configuration.

FastEddieB · Post by **FastEddieB** » Sun Aug 26, 2012 7:50 pm

designrs wrote:You really rather not slip.

Just curious...

...why not?

designrs · Post by **designrs** » Sun Aug 26, 2012 10:31 pm

FastEddieB wrote:
designrs wrote:You really rather not slip.
Just curious...

...why not?

Student here... still practicing slips with my instructor on a BIG runway! LOL
So if I'm going into a smaller runway I'd rather do without the slip... just for now. I realize that slips are a critical technique and I'm working on it!

FastEddieB · Post by **FastEddieB** » Mon Aug 27, 2012 6:02 am

designrs wrote:
Student here... still practicing slips with my instructor on a BIG runway! LOL
So if I'm going into a smaller runway I'd rather do without the slip... just for now. I realize that slips are a critical technique and I'm working on it!

Good on you...

"A man's got to know his limitations" - Clint Eastwood as Dirty Harry

Now make sure you practice them with your instructor until they're just another maneuver. I honestly find myself slipping a bit at some point in nearly every approach - better to be high with lots of tools to get down than to be low and to be 100% dependent on the engine to drag you in.

At the very least I'd be way above those power lines!

designrs · Post by **designrs** » Tue Aug 28, 2012 11:18 am

Thanks Fast Eddie. I like the safety and logic of making slips commonplace... once I finally get the technique down!

FastEddieB · Post by **FastEddieB** » Tue Aug 28, 2012 12:40 pm

You're welcome.

Here's a suggestion you can run by your instructor:

Climb to maybe 6,000' to 8,000'.

Line up with a road or a section line or something, ideally into the wind.

Throttle back to idle, set up best glide and smoothly put in full right rudder while using enough left aileron to not turn and to stay over the road. Lower the nose quite a bit - your instructor can demonstrate.

You'll find that with your foot to the floor you can just "steer" the plane left and right to stay over the road with just aileron.

Once your comfortable in that configuration, coordinate, pause to regroup and then do one in the opposite direction - full left rudder and appropriate right aileron.

Do this a handful of times on a couple consecutive flights and I pretty much guarantee you'll master it.

Good luck!

zaitcev · Post by **zaitcev** » Tue Aug 28, 2012 1:38 pm

FastEddieB wrote:I honestly find myself slipping a bit at some point in nearly every approach

I used to use flaps for that, but now I fly an airplane with no flaps and it made me get used to slips.

drseti · Post by **drseti** » Tue Aug 28, 2012 6:32 pm

zaitcev wrote:now I fly an airplane with no flaps and it made me get used to slips.

I've been flying an Ercoupe a lot lately. It has no flaps. It also has no rudder pedals, so slips are not an option. There's a little trick in that plane to make a steep approach: raise the nose, slow down to 60 MPH or so, and the inboard half of the wing stalls. Now you have very little lift, and descend steeply. Given the extreme wing washout, the outboard half of the wing (where the ailerons are) is at a lower angle of attack and still develops lift, so you have absolute roll control. But, if you're used to flying a conventional airplane, you end up stomping holes in the floorboards with your feet!