Engine on Global Flyer

They're saying the Global Flyer's jet engine burns 102 pounds of fuel an
hour. If that kind of fuel weighs in at 6 pounds per gallon, that's
about 17 gallons an hour, or roughly double what I burn in the little
Cherokees I fly. Then again, the jet propelled the Flyer about 2 times
as fast with a max weight some 4 times greater (again, compared to a
Cherokee). It seems to me that somebody might by in the market for a
plane with characteristics like that...but am I missing something?

--Brent

"Brent" ""b b i g l e r \"@ y a h o o . c o m" wrote in message
...
They're saying the Global Flyer's jet engine burns 102 pounds of fuel an
hour. If that kind of fuel weighs in at 6 pounds per gallon, that's about
17 gallons an hour, or roughly double what I burn in the little Cherokees
I fly. Then again, the jet propelled the Flyer about 2 times as fast with
a max weight some 4 times greater (again, compared to a Cherokee). It
seems to me that somebody might by in the market for a plane with
characteristics like that...but am I missing something?

--Brent

First, that 102 pounds per hour is under a very special set of
circumstances - less than full thrust, and at fairly high altitude - 45,000'
or so. Jets are much more efficient up there. IIRC, the fuel burn was
several times that during the early part of the flight.

As to there being a market for a plane like that, I'm sure there would be
one IF the aircraft didn't come with all of the compromises that give the
Global Flyer its tremendous performance. What limitations, you ask? 100+
foot wingspan isn't very ramp friendly at many small fields. Razor thin
structural margins which would make moderate turbulence a chancey
proposition. The light wing loading and slick design mean the aircraft has
*special* needs in the landing pattern - you saw the drag chutes? Also, the
light weight and large physical size probably make the airplane a real
handful in crosswinds.

There are plenty of other compromises that were made to achieve the GF's
performance, and most of 'em work against using the aircraft for practical
transportation...

KB

Hello Kyle,

There are plenty of other compromises that were made to achieve the GF's
performance, and most of 'em work against using the aircraft for practical
transportation...



Also, it seems that the pilot seat in the Global Flyer must feel like
sitting in a huge jet fuel tank. Not for the faint of heart. But then
again, landing in one of these would certainly turn some heads.

Regards, Joerg

http://www.analogconsultants.com

"Joerg" wrote in message
m...
Also, it seems that the pilot seat in the Global Flyer must feel like
sitting in a huge jet fuel tank. Not for the faint of heart. But then
again, landing in one of these would certainly turn some heads.

Although the Global Flyer took this concept to extremes, one must remember
that sitting in the average airliner isn't all that far from sitting in a
big fuel tank. The wings are full of it, not to mention various other tanks!
I guess people just don't think about that too much, particularly the
nervous flyers :-)

D.

Hello David,

Although the Global Flyer took this concept to extremes, one must remember
that sitting in the average airliner isn't all that far from sitting in a
big fuel tank. The wings are full of it, not to mention various other tanks!
I guess people just don't think about that too much, particularly the
nervous flyers :-)



That is true. Even in a regular pickup truck you may be literally
sitting above 40 Gallons of gasoline. One side impact can send that off
into a huge blaze. With nervous flyers it might be best not to talk
about this stuff when sitting next to them. They'd only become more nervous.

Then there are a couple huge engines hanging under the fuel filled
wings. And occasionally one of these goes kaputt. That happened when I
was a passenger on a flight while still over the atlantic, leaving only
one engine to fly on. I believe that the maintenance crew also had to
massage all those clenched armrests back into shape after the landing.
But at least nobody freaked out and despite the uneven thrust the pilot
almost made the landing a perfect greaser. That must have been a white
knuckle event.

Regards, Joerg

http://www.analogconsultants.com

"Joerg" wrote in message
om...
Then there are a couple huge engines hanging under the fuel filled wings.
And occasionally one of these goes kaputt. That happened when I was a
passenger on a flight while still over the atlantic, leaving only one
engine to fly on. I believe that the maintenance crew also had to massage
all those clenched armrests back into shape after the landing. But at
least nobody freaked out and despite the uneven thrust the pilot almost
made the landing a perfect greaser. That must have been a white knuckle
event.

According to a friend of mine who used to fly helicopters to oil rigs, it's
not exactly a white knuckle ride, but there is always a bit of a nagging
thought in the mind of the pilots along the lines of "Unless we're 100% sure
why that engine broke, we can't be sure the other one won't" and so it's
always a relief when you get it on the ground. My friend had a gearbox break
one day, but there were two engines and two gearboxes, and the second one
worked fine and the flight went off safely.

You can't be sure, after all, that whatever caused the fault in one engine
won't do so in another. I remember reading of an incident in a three-engine
aircraft (DC-10?) where a mechanic changed the magnetic chip detectors
(little screw-in plugs that attract particles of metal that have worn off
the engine so you can analyse them) and replaced them with new ones that
didn't have their rubber seals fitted. So all three engines ran low on oil
some way into the flight. Initially they thought there was a spurious oil
leak (ruptured/worn pipe or whatever) in the engine that failed first, only
to see the oil pressure drop on the other two first!

D.

In article ,
Brent ""b b i g l e r \"@ y a h o o . c o m" wrote:

They're saying the Global Flyer's jet engine burns 102 pounds of fuel an
hour. If that kind of fuel weighs in at 6 pounds per gallon, that's
about 17 gallons an hour, or roughly double what I burn in the little
Cherokees I fly. Then again, the jet propelled the Flyer about 2 times
as fast with a max weight some 4 times greater (again, compared to a
Cherokee). It seems to me that somebody might by in the market for a
plane with characteristics like that...but am I missing something?

And look at the altitude they got out of that aircraft. They
were consistently in the 40,000 foot range.

-john-

--
================================================== ====================
John A. Weeks III 952-432-2708
Newave Communications http://www.johnweeks.com
================================================== ====================

What in the hell don't you understand about the achievements of
"experimental" aircraft"? Why do you think that we do what we do and then
release our results to the airplane building world?

Jim



"Brent" ""b b i g l e r \"@ y a h o o . c o m" wrote in message
...
They're saying the Global Flyer's jet engine burns 102 pounds of fuel an
hour. If that kind of fuel weighs in at 6 pounds per gallon, that's about
17 gallons an hour, or roughly double what I burn in the little Cherokees
I fly. Then again, the jet propelled the Flyer about 2 times as fast with
a max weight some 4 times greater (again, compared to a Cherokee). It
seems to me that somebody might by in the market for a plane with
characteristics like that...but am I missing something?

--Brent