Piper loses propellor in Aspen

Aspen elev. 7,820 ft.

Glide began at 16,000 ft

net glide = 8180 ft.

8180 / 12.5 = 654 fpm loss

90 knots = approx 81 mph, transposes to a "16.75" minute glide

654 fpm loss, for 16.75 minutes = 10,954 ft.

From where, did he get the extra 2,774.5 feet ??

Mountain updrafts?

Or .....is there an error in my math??

Seriously.
This doesn't make sense to me... as a fairly new "bumpy flatland" pilot.

 

Maybe if we change the problem to a glide ratio calc.

12.5 miles = 66,000 feet

The pilot lost approximately 8180 feet in altitude.


so the glide ratio here: 66,000/8180 = 8.07:1


Which isn't terribly out of line with the published glide ratios of other singles -- though depending on who you ask the estimates will range between 6:1 and 10:1.

Add in a the benefits of not having a windmilling prop and it seems like a good (possibly even conservative) estimate of the Malibu's glide ratio at best glide speed.

 

You guys scare me but I have to go with Boffin. That glide ratio seems to add up with what I know ( don't know ) about the modern Spam Can.. Anyway, he did a damn good job of getting the airplane down and safe. In what flying I have done over the years I have never had an engine failure. I have experienced " my failures" which are just as bad. I have had everything up front from R1830's down to two cylinder Aeronca's and Model A's and I have been lucky.

 

Calculating glide ratio will not tell the full story of exactly how skillful and fortunate this pilot was.

Living in Colorado and having flown into Aspen on many an occasion the issue is not simply glide ratio but obstruction clearance. Obstructions being in the form of cumulus granite!

Just north of the airport the terrain rises steeply to 9000 ft in as little as 4 miles and to 10,500 feet in 7 miles. Now add 1000 to 1,500 feet to that to assure safe obsticle clearance and you find the picture changes drastically. It makes no difference what glide ratio the aircraft is capable of if that glide needs to pass THROUGH intervening mountains!

In fact, he was fortunate to be flying a rather high performance single so as to have been able to gain altitude to 16,000 feet as rapidly as he did. Otherwise he would have been S.O.L

Most singles taking off from Aspen need to turn to the west to follow the ridge while climbing until they can make a right hand U-turn where the ridge tapers down and continue climbing along the roaring fork river eastbound now on the north side of the ridge. Add density altitude considerations into the mix and you can see that Aspen can be a bit of a challange under adverse circumstances.

Planeflyr

 

In addition to the change in drag afforded by the lack of a windmilling propeller, the reduced weight and the radical shift to an aft CG will also have a dramatic effect on glide ratio.

 

Now there's a theory that's hard to argue with!

Salve . . . Roy

 

Here Here, the Lord is good.

 

Here, Here, the Lord is good.

 

Indeed He is.

I witnessed the aftermath of an emergency landing in Laurel MD on Saturday. A light sport aircraft was forced to use its ballistic recovery parachute after (here reports conflict) the pilot either experienced chest pains or mechanical problems. Preliminary reports are that the pilot and a bystander were treated for non-life-threatening injuries.

 

That's just like when someone escapes from a dangerous situation,
ie an auto accident you avoided

People say "Gee, You were ............. "LUCKY"!


....... never taking into account the skill you used to avoid the danger.

But if you didn't escape.....But did everything humanly possible, yet still got ....those same people, no matter what the reason, say

"You should have been more careful!"

This, has always irked me !!!!

Arrrrrrggggghhhhh!!!

Charlie