What GA needs

"Andrew Sarangan" wrote in message
ups.com...
This is a follow-on to the various discussions on the future of GA.

Why aren't the kids who grew up with cell phones and iPods not
interested in aviation?

One key factor is the antiquated airplanes we fly. If we could only
drive a1975 Chevy Nova or something similar, with bolted down wooden
panels and foggy instruments, I doubt many teenagers would be earger
to get their drivers license.

The second aspect is the fascination pilots seem to have with war
equipment, and the yearning for the 'good ol days'. Many pilots look
at a WW2 airplane like a B17 as if it were a technological marvel.
That may be true, but it just doesn't connect with the new generation.
Even though I am not from the iPod generation, I too found this
fascination with war equipment rather strange. Perhaps it is because
no one in my anscestry participated in the war.

How many kids do you see hanging around at antique car shows? Airports
are not too far from being an antique museum.

Aviation technology has marched on in great strides in the past 50
years. But almost all of the modernization has occured due to the
advancement in electronics. This is the only aspect that keeps some of
us still interested in aviation. That includes VOR, GPS, satellite
weather, flight planning tools, electronic charts, glass panels etc..
The mechanical aspects have been stagnant. All these modern
electronics are still housed in ancient aluminum panels that are
riveted togother. They creak and vibrate, and the engines consume
leaded fuel and puff out smoke and oil, and have frightening gas
mileage.

In order to appeal to the next generation, this is what I think we
need:
- a small turbine engine suitable for GA aircraft with fewer moving
parts and smoother operation
- gas mileage comparable to an SUV
- a fully composite airframe
- molded aesthetic interiors
- cost about 2-3x the price of a luxury car

The list is very ambitious, but we are on the right path with LSA.
What is still seriously lacking is the powerplant.
I would really like to see is a small turbine engine. I don't mean
salvaged APUs. It has to be something that is designed from the bottom
up as a GA powerplant.

Any comments?


"Small Turbine" and "Gas mileage" - you only get one - the thermodynamics
just don't support both without real exotic materials.

Other than that, though...


--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

On Sep 10, 6:28 pm, "Capt. Geoffrey Thorpe" The Sea Hawk at wow way
d0t com wrote:
"Andrew Sarangan" wrote in message

ups.com...





This is a follow-on to the various discussions on the future of GA.

Why aren't the kids who grew up with cell phones and iPods not
interested in aviation?

One key factor is the antiquated airplanes we fly. If we could only
drive a1975 Chevy Nova or something similar, with bolted down wooden
panels and foggy instruments, I doubt many teenagers would be earger
to get their drivers license.

The second aspect is the fascination pilots seem to have with war
equipment, and the yearning for the 'good ol days'. Many pilots look
at a WW2 airplane like a B17 as if it were a technological marvel.
That may be true, but it just doesn't connect with the new generation.
Even though I am not from the iPod generation, I too found this
fascination with war equipment rather strange. Perhaps it is because
no one in my anscestry participated in the war.

How many kids do you see hanging around at antique car shows? Airports
are not too far from being an antique museum.

Aviation technology has marched on in great strides in the past 50
years. But almost all of the modernization has occured due to the
advancement in electronics. This is the only aspect that keeps some of
us still interested in aviation. That includes VOR, GPS, satellite
weather, flight planning tools, electronic charts, glass panels etc..
The mechanical aspects have been stagnant. All these modern
electronics are still housed in ancient aluminum panels that are
riveted togother. They creak and vibrate, and the engines consume
leaded fuel and puff out smoke and oil, and have frightening gas
mileage.

In order to appeal to the next generation, this is what I think we
need:
- a small turbine engine suitable for GA aircraft with fewer moving
parts and smoother operation
- gas mileage comparable to an SUV
- a fully composite airframe
- molded aesthetic interiors
- cost about 2-3x the price of a luxury car

The list is very ambitious, but we are on the right path with LSA.
What is still seriously lacking is the powerplant.
I would really like to see is a small turbine engine. I don't mean
salvaged APUs. It has to be something that is designed from the bottom
up as a GA powerplant.

Any comments?

"Small Turbine" and "Gas mileage" - you only get one - the thermodynamics
just don't support both without real exotic materials.

Other than that, though...

--

I have heard that argument many times, but I have never seen that
thermodynamic argument presented. I just borrowed the book on Aircraft
Gas Turbine Engines from the library and plan to read it to find out
what the real story is. My suspicion is that the limitation is in the
materials, not thermodynamics. It may take a significant investment,
but if the military is also interested in similar things it won't be
that hard to find the R&D suppport. I've heard that small turbines are
of interest to the Air Force for potential use in UAVs. A UAV and a
small GA airplane are not that far apart. In fact, the predator is
using the Rotax 914 engine which is a very popular GA engine. A small
turbine may sound far fetched now, but I am sure GPS also sounded far
fetched 20 years ago, but became commonplace after heavy military
investment.

Having said that, I know of at least two companies working on small
turbines. One is Innodyn, and the other one is M-dot. The latter one I
believe has some DoD contracts to be build turbines for UAVs. I doubt
these companies would even exist if the basic physics is flawed.

"Andrew Sarangan" wrote in message
oups.com...
On Sep 10, 6:28 pm, "Capt. Geoffrey Thorpe" The Sea Hawk at wow way
d0t com wrote:
...
"Small Turbine" and "Gas mileage" - you only get one - the thermodynamics
just don't support both without real exotic materials.

Other than that, though...

--

I have heard that argument many times, but I have never seen that
thermodynamic argument presented. I just borrowed the book on Aircraft
Gas Turbine Engines from the library and plan to read it to find out
what the real story is. My suspicion is that the limitation is in the
materials, not thermodynamics. It may take a significant investment,

That's why I said "without real exotic materials"

The materials limit the maximum termperatures. The maximum temperatures
limit the maximum efficiency. Also "small" (and I assume "reasonable cost")
rule out regenerators to capture some of the waste heat (common on
stationary applications)

but if the military is also interested in similar things it won't be
that hard to find the R&D suppport. I've heard that small turbines are
of interest to the Air Force for potential use in UAVs. A UAV and a
small GA airplane are not that far apart. In fact, the predator is

True, but the military tends to care less about fuel cost and more about
being able to use the same fuel in everything so if you have fuel, you have
fuel.

There were a number of programs in the 60's for turbines and direct
injection piston engines that would run on "any fuel' that was available...

...
Having said that, I know of at least two companies working on small
turbines. One is Innodyn, and the other one is M-dot. The latter one I
believe has some DoD contracts to be build turbines for UAVs. I doubt
these companies would even exist if the basic physics is flawed.


Nothing wrong with the physics. Small turbines work. And for some
applications they have big adavantages. Fuel quantity per horsepower-hour,
however, isn't one of them.

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

"Capt. Geoffrey Thorpe" The Sea Hawk at wow way d0t com wrote in message
news:BuCdncDCBfMie3jbnZ2dnUVZ_jadnZ2d@wideopenwest .com...
"Andrew Sarangan" wrote in message
oups.com...


Nothing wrong with the physics. Small turbines work. And for some
applications they have big adavantages. Fuel quantity per horsepower-hour,
however, isn't one of them.

The "New Wave" is much more likely to be diesel, especially given the 100LL
"crisis".

Capt. Geoffrey Thorpe wrote:


Nothing wrong with the physics. Small turbines work. And for some
applications they have big adavantages. Fuel quantity per horsepower-hour,
however, isn't one of them.


Agreed. Turbines are most efficient well above normal GA altitudes. At
common GA altitudes they suck large quantities of fuel. A turbine powered
Luscombe project used to be based at my field. The speed and climb were
slightly better than a piston powered Luscombe, but the range was
dramatically shorter.

While you can burn almost anything in them, you should plan on burning a
lot of it. That was also one of the downfalls of the early turbine powered
cars (besides the initial expense).

John Galban=====N4BQ (PA28-180)

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums...ation/200709/1

"JGalban via AviationKB.com" u32749@uwe wrote in message
news:7814f2bf2e916@uwe...
Capt. Geoffrey Thorpe wrote:


Nothing wrong with the physics. Small turbines work. And for some
applications they have big adavantages. Fuel quantity per horsepower-hour,
however, isn't one of them.


Agreed. Turbines are most efficient well above normal GA altitudes. At
common GA altitudes they suck large quantities of fuel. A turbine
powered
Luscombe project used to be based at my field. The speed and climb were
slightly better than a piston powered Luscombe, but the range was
dramatically shorter.

A Luscombe needs a turbine engine like a carp needs an outboard motor.

On Mon, 10 Sep 2007 17:06:34 -0700, Andrew Sarangan
wrote in
.com:

A small turbine may sound far fetched now, but ...

There seem to be lots of small turbine engines available now, and
they're getting bigger:


http://www.gasturbine.pwp.blueyonder.co.uk/page2.htm

Cobra Facts and Figures
Thrust............................................ ....... ...163N
Weight............................................ .........3.1 Kg
Pressure ratio at max rpm.........................3.0
Max rpm..............................................1 05,000 rpm
Idle speed............................................3 0,000 rpm
Max exhaust gas temp..............................640 degrees C
Mass flow.............................................. ..0.31 kg/s
Specific Fuel Consumption (Propane).......0.8 Kg/N/Hr
Lubrication.......Total loss system, Aeroshell 390 pressurised
from compressor bleed.
length including jet pipe............................444 mm
Maximum width.......................................197 mm

The Worlds Smallest Jet Aircraft Powered by two Cobra Engines


--------------------------------------------------
http://www.gtba.co.uk/
THE GAS TURBINE BUILDERS ASSOCIATION

http://www.gtba.co.uk/engine_designs...8e9bec894a 04
Homebuilt engine designs


-------------------------------------
http://www.wrenturbines.co.uk/
http://www.wrenturbines.co.uk/product.php?pid=6
XL200 - AutostartStatistics Thrust 15kg
(33lbs)
Size 274mm x 120mm
(11in x 4.8in)
Weight 1800g
(4lbs)
Fuel Consumption 494ml/min
Advanced Statistics Click Here
Buy This Package Now for £2300
------------------

http://www.swbturbines.com/
http://www.swbturbines.com/products/products.htm
SWB-100SWB Proudly Announces the birth of our newest turbine the
SWB-100. Actually producing 107 lb/ft thrust, this is one of the
largest and most powerful turbines produced by SWB. This turbine
is designed for professional large scale UAV applications. The
engine has been extensively tested in our test cell using industry
standard turbine testing procedures. The testing and qualification
stages of this turbine engine are done. The engine is available
for delivery, call today for more details.

-----------------------------------------

http://www.heward-microjets.co.uk/en...wasp1h20.shtml
WASP 1 H20 SPECIFICATIONS

When correctly constructed:
Max Thrust:
18-20 lb
8.1-9.07 kg

Engine weight:
2 lb
950 gr

Engine weight with starter:
2.4 lb
1090 gr

Max RPM:
148,000 RPM

Fuel consumption @ max RPM:
260 ml/min
200 gr/min

Diameter:
3.74 in
95 mm

Length:
6.69 in
175 mm

Length with starter:
9.64 in
245 mm


The Wasp 1 H20 is specially designed as a homebuild engine. The
complete kit comes with a comprehensive and detailed Drawings and
Instruction Manual which gives full instructions for the
construction of each and every part of the engine. The
construction manual can be purchased seperately and delivered by
post or emailed as a PDF.

If you do not wish to make the parts yourself, you may purchase
them either individually or as a set. All parts are fully machined
and ready for assembly. The price list of parts are as follows:
...

The complete kit package comprising all parts required to build a
Wasp 1 engine is priced at ONLY £899. This introductory offer is
for a limited time only. Place your orders early to avoid
disappointment.

------------------------------

http://www.amtjets.com/mk2hpes/mk2-hp.html

Specifications Olympus HP E-start:

Engine diameter:
Engine length:
Engine weight:
Electronic Control Unit:
Fuel pump:
Gas bottle:
Flight Battery:
2 solenoid valves:
System airborne weight:

130 mm / 5.1 inches
375 mm / 14.7 inches
2850 Gram / 100 oz
110 Gram / 3.9 oz
170 Gram / 6.0 oz
95 Gram / 3.3 oz
350 Gram / 12.4 oz
80 Gram / 2.8 oz
---------------------------------
3685 Gram / 128.4 oz
Thrust @ max. rpm@ STP (15 Deg.C/1013 Mbar):
Maximum RPM:
Idle RPM:
Mass flow @ max. rpm:
Normal EGT :
Maximum EGT:
Fuel consumption @ max. rpm:
Fuel type:
Throttle response from Idle RPM to Max RPM:
Throttle response from 30% throttle to Max RPM:
Throttle response from 50% throttle to Max RPM:

E-start time:
23,5 Kilogram force / 51.7 Lbf
108,500
36,000
450 gr/sec. / 0.99 Lb/sec.
700 °C / 1290 °F
775 °C / 1380 °F
640 gr/min. / 22.5 oz/min.
JP-4/paraffin/Jet A1, mixed with 4,5% Oil
3.5 Seconds.
1.5 Seconds.
0.5 Second.

10-15 seconds*

* Fuel system primed from last engine run.
Time measured from ignition to reaching idle RPM.
Fully charged Nicad battery.
Propane as starting gas.
€ 4.705,00

---------------------------------

"Andrew Sarangan" wrote in message
oups.com...
On Sep 10, 6:28 pm, "Capt. Geoffrey Thorpe" The Sea Hawk at wow way
d0t com wrote:

"Small Turbine" and "Gas mileage" - you only get one - the thermodynamics
just don't support both without real exotic materials.

Other than that, though...

--

I have heard that argument many times, but I have never seen that
thermodynamic argument presented. I just borrowed the book on Aircraft
Gas Turbine Engines from the library and plan to read it to find out
what the real story is. My suspicion is that the limitation is in the
materials, not thermodynamics.

Umm...that's what he said: "...real exotic materials".


It may take a significant investment,
but if the military is also interested in similar things it won't be
that hard to find the R&D suppport. I've heard that small turbines are
of interest to the Air Force for potential use in UAVs. A UAV and a
small GA airplane are not that far apart. In fact, the predator is
using the Rotax 914 engine which is a very popular GA engine. A small
turbine may sound far fetched now, but I am sure GPS also sounded far
fetched 20 years ago, but became commonplace after heavy military
investment.

Having said that, I know of at least two companies working on small
turbines. One is Innodyn, and the other one is M-dot. The latter one I
believe has some DoD contracts to be build turbines for UAVs. I doubt
these companies would even exist if the basic physics is flawed.

It's not the physics, it's the COST of those PHYSICS.

Andrew Sarangan writes:

I have heard that argument many times, but I have never seen that
thermodynamic argument presented. I just borrowed the book on Aircraft
Gas Turbine Engines from the library and plan to read it to find out
what the real story is. My suspicion is that the limitation is in the
materials, not thermodynamics.

Measure the heat of a gas turbine exhaust; the difference between that and
ambient inlet temperature is wasted energy. An ideal turbine would extract so
much energy from the heat of combustion that the exhaust would barely be warm,
but we're a long way from a turbine like that.

A small
turbine may sound far fetched now, but I am sure GPS also sounded far
fetched 20 years ago, but became commonplace after heavy military
investment.

Actually, the principles behind GPS were known and accepted half a century
ago. It just took a long time to get a working system perfected--just as
improvements in jet engines tend to be gradual.

Having said that, I know of at least two companies working on small
turbines. One is Innodyn, and the other one is M-dot. The latter one I
believe has some DoD contracts to be build turbines for UAVs. I doubt
these companies would even exist if the basic physics is flawed.

Low efficiency can be compensated by other advantages.

On Sep 10, 3:07 pm, Andrew Sarangan wrote:

Any comments?

First, my "kid" credentials: 34 years old, heavy internet user, geek
extraordinaire. I'm an instrument-rated private pilot. I think it's
also relevant that my pilot training was self-financed starting at the
age of 26 or so. I am not a home owner, not an aircraft owner, not a
business owner, not independently wealthy.

I learned to fly because it was a dream I had since I was a boy, and
during the boom years in Silicon Valley I was making enough (salary,
not equity) to be able to learn to fly. I rent from a local club in
Palo Alto (Sundance) that, like almost all such clubs, has mostly the
so-called grumpy old men members. I have never taken the controls of
an aircraft that did not smell like somebody's grandpa.

Even as someone who is *into* aviation, it is simply not affordable,
and its also not all that useful. I live in California, and there are
airports galore (I've been to a *lot* of them!) but when I get to the
airport I am usually stuck. Renting a car is a necessity, and often
enough not even a possibility. Cost and utility are interrelated, of
course. I've got the instrument rating, and I keep it up -- legally --
but seriously, it would cost a lot of money to keep it up to a level
of proficiency to make it truly useful. And the equipment that I can
rent for $100/hr isn't exactly hard-IFR faith inspiring, either. I
have never flown behind a panel mount GPS. I dutifully pop all those
new RNAV approaches into my book every two weeks, and wonder who the
hell is able to use these? Nobody in my club!

Of course, it's easier to come up with problems than solutions. I will
tell you one thing that is not a solution: Cirrus aircraft and their
like. GA is in a CLASSIC death-spiral: companies are moving to their
high-end customers to maintain adequate margins. Cirrus's and others'
$450k+ aircraft are not doing a damned bit to save GA. This trend to
make new, high tech, high-end toys will only speed the erasure of GA.
On the other hand, Garmin *is* doing something to help GA. The fact
is, the new glass cockpits are much more capable than the old steam
gauges (or so I've read ) but cost about the same -- or less. That
is real progress -- getting aircraft back onto a technology curve.

If Ly/Co could somehow get back on a real product improvement curve,
that would be something to hope for, too. I don't know if turbine is
the solution. I'd say something more akin to Jabiru/Rotax is.

The LSAs, well, since they're all hovering around six figures and
above, I'm not sure who they're supposed to appeal to, either.

There is another thing that could help GA. Imagine this (admittedly
not particularly well thought-out) scenario:
-- wealthy boomers eventually die out
-- without stream of wealthy customers, GA airframe manufacturers
also die out
-- industry goes into a coma for a decade or so
-- investors re-discover aviation, buy assets of said manufacturers
for pennies on the dollar
-- new, more modest A/C designs emerge that more people can
participate in
-- GA, reborn as something that the reasonably affluent (not just
rich) can participate in

This only works if in the meantime airport closures, user fees,
insurance requirements, etc, don't make a revival impossible.

My $0.0n,
-- dave j