Glide ratios in a Super Cub
- Thread starter Dnh98221
- Start date
courierguy
MEMBER
Inkom, Idaho
As one who has done a fair bit of dead stick ridge soaring, (in a RANS S-7S, not a SC) I'm going to hazard a guess: 7 to 1? Work calls, I'll read your article tonight.
frequent_flyer
Registered User
Arizona, USA
Makes my eyes and head hurt so I gave up trying to read it. How did you manage to make a PDF so fuzzy?
cubdriver2
FRIEND
upstate NY
I always was told radius below looking at horizontal jury strut brace was a quick guide
Glenn
Glenn
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mvivion
SPONSOR
Bozeman,MT
First, look right under you. THEN, if nothing there, look VERY close to the plane.
Do you KNOW what the wind is at altitude? Do you know what the wind is on the surface?
If you try to stretch a glide, either of those, and a dozen other variables can bite you.
And, sometimes, the best solution is right under you.
MTV
Do you KNOW what the wind is at altitude? Do you know what the wind is on the surface?
If you try to stretch a glide, either of those, and a dozen other variables can bite you.
And, sometimes, the best solution is right under you.
MTV
frequent_flyer
Registered User
Arizona, USA
Perhaps important to distinguish between "as far as you will make it" and "as far as you can make it". At any speed and with any airmass motion there will be a spot that doesn't move. Doesn't mean that spot is a far as you could glide if you flew best glide speed for the conditions. POH best glide speed is for max gross, zero wind, and zero airmass vertical motion. These are not usually the conditions that exist when the engine stops.
Farmer Hank
SPONSOR
Kalispell, Montana
To confirm what MTV wrote: I took a Forest Service check ride out of Missoula 50 years ago. The inspector suddenly said “Engine failure!” I rolled the 206 sharply to the left. There was a strip right under me! End of emergency.
Farmer Hank
SPONSOR
Kalispell, Montana
A friend of mine took a check ride in a 747 sim. They flew under the Golden Gate Bridge. He was admonished to fly very low: “Do you know how high your tail is!” Then the inspector pulled all four engines to idle. “What are you going to do now!” The plane had enough speed and glide ratio to return safely to SFO.
frequent_flyer
Registered User
Arizona, USA
I knocked the tail off an MD-11 doing the same. (Lots of time in sim cabs doing engineering development and there was sometimes time to play)
JP
FOUNDER
The Big Woods of Maine
All good considerations. This is as far as I could make it. Established best glide (55 for the 11) while picking best spot upwind and uphill within a 45 cone, and down we went. Right on the spot.
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frequent_flyer
Registered User
Arizona, USA
mvivion
SPONSOR
Bozeman,MT
As suggested earlier, you MAY have to make a turn into the wind, once you get to your chosen landing site. A tailwind on landing off airport can cause a LOT of damage…..to the occupants. How far you can glide in a straight line is just one PART of an engine out emergency.
MTV
MTV
JP
FOUNDER
The Big Woods of Maine
For this practice session I was in luck; 5 minutes prior I was over the endless woods and headed towards even more, and had just left a small, tight strip on the edge of a lake with lots of lovely obstacles.
AZ is stunning and I hope to get back at some point.
Steve Pierce
BENEFACTOR
Graham, TX
PDFs uploaded here get fuzzy for some reason. Might email it to SJ and see if he can post it.
courierguy
MEMBER
Inkom, Idaho
The S-7, with 29" tires, dead stick performance probably about the same as a SC. 1 notch of flaps, indicated speed about 55 mph I think. https://youtu.be/PkxFzQE2gEo
On short final, it was looking about right to continue the dead stick to a landing, which I've threatened to do on my strip but haven't yet, I'll save it for when I need it. Plus I'm scared.
On short final, it was looking about right to continue the dead stick to a landing, which I've threatened to do on my strip but haven't yet, I'll save it for when I need it. Plus I'm scared.
cubflier
MEMBER
Palmer, AK
Flying over cold water that will kill you if you take a swim will cause you to set reasonable glide ratio expectations. I use 1 mile of glide per 1000 ft of altitude.
Keeps the thought process simple. If I cross between two islands I try to cross at half the distance times 1000 ft. A 16 mile water crossing means cross at 8000 ft. It gives me time for all the stuff that will happen when the engine gets quiet.
Jerry
Keeps the thought process simple. If I cross between two islands I try to cross at half the distance times 1000 ft. A 16 mile water crossing means cross at 8000 ft. It gives me time for all the stuff that will happen when the engine gets quiet.
Jerry
hotrod180
FRIEND
Port Townsend, WA
Good thinking.
Cessna indicates about an 8:1 glide ratio,
so about 1.5 miles per 1000' of altitude.
Of course, that's if you are right on the mark for the best glide speed *at your actual weight*,
and doesn't account for time spent turning to a new course, stabilizing your airspeed, etc.
So your 1 mile:1000' is probably a lot closer to reality.
mvivion
SPONSOR
Bozeman,MT
You must be getting old like me Jerry! I can remember vividly many crossings of Shelikof Straight, wishing I could get a bit higher, like ten thousand feet higher….but I was young then, and perhaps not quite as…..er bright?
Good advice, in any case.
MTV
jnorris
MEMBER
Wisconsin
This is sage advice. I've spent a fair amount of time flying high-drag aircraft, and have learned that the only place that you are absolutely, positively sure you can make is that which is directly below you, or nearly so. That's where I always start! If you have to start looking farther and farther away, your chance of success diminishes pretty quickly.
Eddy Lewis
SPONSOR
Cortez Colorado
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bob turner
Registered User
Where were you guys when the discussion was single engine along the coast from Seattle to Anchorage? That run scared me looking at it from a jet at 35,000 feet! Talk about cold water and no beach . . .
mvivion
SPONSOR
Bozeman,MT
There is a balance between stupid and trusting your engine. I had an engine failure in a very inhospitable place. I landed a place that was more hospitable, but I guarantee nobody here would land there intentionally. Pretty well used up the plane. That evening I went to dinner with Gina and relatives of hers she hadn’t seen for years. I’m sure they figure Gina married a wino.
You just have to walk, or crawl away. You can get another plane. Land slow, and Use the plane up and it’ll likely save you.
MTV
You just have to walk, or crawl away. You can get another plane. Land slow, and Use the plane up and it’ll likely save you.
MTV
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BC12D-4-85
SPONSOR
Fairbanks, AK.
Mike, didn't the plane do a full rollover coming to rest upright?
Gary
Gary
