Why Are Gasoline-Like Fuels Favored For Aircraft?

[CHANGE username to westes]

Since taking up aviation as a hobby, I have wondered why gasoline, and
similar oil-derived liquid fuels, have become the defacto standard for all
forms of general aviation and commercial and military aircraft. Comparing
Jet fuel to something like natural gas, Jet fuel is four times as expensive.
Liquid fuels are extremely heavy, and certainly airplanes do not need extra
weight.

This leads me to wonder why haven't engines been commercialized that can
burn gas-based fuels? Is the only reason safety, because of the
explosive nature of gas fuels like natural gas or hydrogen?

Isn't there some way you could use two separate gases, which in their
separate state are inert, but combined together under high pressure, become
explosive? Such a combination would not ignite if the airplane crashed
(you could separate the gases into separate containers on each side of the
airplane, at the wingtips), but in controlled injection into a high pressure
compartment could be made explosive in a controlled way, in a very limited
space.

Think how much fuel is being wasted each day on airplanes, simply to support
the extra weight required to carry the fuel itself. Think how dangerous
airplanes are during relatively survivable impacts to the ground, primarily
because they are gasoline bombs. I would be very interested to read about
efforts to develop gas based engines for general aviation or commercial
aircraft. I would appreciate any pointers to web sites or books.

--
Will

NOTE: To reply, CHANGE the username to westes AT earthbroadcast.com

[John Mullen]

"CHANGE username to westes" > wrote in
message ...
> Since taking up aviation as a hobby, I have wondered why gasoline, and
> similar oil-derived liquid fuels, have become the defacto standard for all
> forms of general aviation and commercial and military aircraft.
Comparing
> Jet fuel to something like natural gas, Jet fuel is four times as
expensive.
> Liquid fuels are extremely heavy, and certainly airplanes do not need
extra
> weight.
>
> This leads me to wonder why haven't engines been commercialized that can
> burn gas-based fuels? Is the only reason safety, because of the
> explosive nature of gas fuels like natural gas or hydrogen?
>
> Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure,
become
> explosive? Such a combination would not ignite if the airplane crashed
> (you could separate the gases into separate containers on each side of the
> airplane, at the wingtips), but in controlled injection into a high
pressure
> compartment could be made explosive in a controlled way, in a very limited
> space.
>
> Think how much fuel is being wasted each day on airplanes, simply to
support
> the extra weight required to carry the fuel itself. Think how dangerous
> airplanes are during relatively survivable impacts to the ground,
primarily
> because they are gasoline bombs. I would be very interested to read
about
> efforts to develop gas based engines for general aviation or commercial
> aircraft. I would appreciate any pointers to web sites or books.

Your mistake is to assume that gases are always lighter than liquid fuels.
Obviously they are under normal pressure but to be any use as fuels for a
vehicle they have to be compressed and/or liquified. This negates any
apparent weight gains. You also need to factor in the weight of insulation
and/or pressure vessels.

Weight for weight petrol and kerosine are very energetic indeed.

One of the greatest challenges facing us will be how to make hydrogen into a
usable form for cars and aircraft as the oil reserves we currently use begin
to run out over the next fifty years or so.

John

[Keith Willshaw]

"CHANGE username to westes" > wrote in
message ...
> Since taking up aviation as a hobby, I have wondered why gasoline, and
> similar oil-derived liquid fuels, have become the defacto standard for all
> forms of general aviation and commercial and military aircraft.
Comparing
> Jet fuel to something like natural gas, Jet fuel is four times as
expensive.
> Liquid fuels are extremely heavy, and certainly airplanes do not need
extra
> weight.
>
> This leads me to wonder why haven't engines been commercialized that can
> burn gas-based fuels? Is the only reason safety, because of the
> explosive nature of gas fuels like natural gas or hydrogen?

First thing to get clear

Gasoline is NOT repeat NOT favored for military aircraft

Now to address gas based fuels

Gas is by its nature volatile and a severe fire hazard, not just
for the aircraft but for the ground base/carrier. With a liquid fuel
you first have to gasify it to make it burn, thats what the wick is
for on an oil lamp or the carburettor on a car engine, with gas based fuels
you are already there

There are other problems though.

1) Gas , even when liquified, takes up more volume for the same
calorific value

2) The heavy containers needed for compressed or liquified gas
are a severe weight penalty

>
> Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure,
become
> explosive? Such a combination would not ignite if the airplane crashed
> (you could separate the gases into separate containers on each side of the
> airplane, at the wingtips), but in controlled injection into a high
pressure
> compartment could be made explosive in a controlled way, in a very limited
> space.
>

There's none that I know of and if there were you just introduced
another level of complexity and extra weight

> Think how much fuel is being wasted each day on airplanes, simply to
support
> the extra weight required to carry the fuel itself. Think how dangerous
> airplanes are during relatively survivable impacts to the ground,
primarily
> because they are gasoline bombs. I would be very interested to read
about
> efforts to develop gas based engines for general aviation or commercial
> aircraft. I would appreciate any pointers to web sites or books.
>
>
Modern aircraft dont use gasoline as fuel, they use relatively
inert grades of Kerosene stable enough that its hard to
light with a match unless you provide a wick or vaporise
the stuff.. Somehow I doubt any flammable gas would be safer.

I KNOW both LPG nor Hydrogen are more dangerous.

Keith

[B2431]

>From: "Keith Willshaw"

<snip>

>Modern aircraft dont use gasoline as fuel, they use relatively
>inert grades of Kerosene

<snip>

>Keith
>
They don't? Recips tend to use gasoline. There are plenty of modern aircraft
that use recips.

Turbines use kerosene equivelents.

Dan, U. S. Air Force

[Keith Willshaw]

"B2431" > wrote in message
...
> >From: "Keith Willshaw"
>
> <snip>
>
> >Modern aircraft dont use gasoline as fuel, they use relatively
> >inert grades of Kerosene
>
> <snip>
>
> >Keith
> >
> They don't? Recips tend to use gasoline. There are plenty of modern
aircraft
> that use recips.
>

Mostly light GA types and damn few military ones .

> Turbines use kerosene equivelents.
>

Which needless to say isnt gasoline-like.

Keith

[Harry Andreas]

In article >, "CHANGE username to
westes" > wrote:

> Since taking up aviation as a hobby, I have wondered why gasoline, and
> similar oil-derived liquid fuels, have become the defacto standard for all
> forms of general aviation and commercial and military aircraft. Comparing
> Jet fuel to something like natural gas, Jet fuel is four times as expensive.
> Liquid fuels are extremely heavy, and certainly airplanes do not need extra
> weight.
>
> This leads me to wonder why haven't engines been commercialized that can
> burn gas-based fuels? Is the only reason safety, because of the
> explosive nature of gas fuels like natural gas or hydrogen?
>
> Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure, become
> explosive? Such a combination would not ignite if the airplane crashed
> (you could separate the gases into separate containers on each side of the
> airplane, at the wingtips), but in controlled injection into a high pressure
> compartment could be made explosive in a controlled way, in a very limited
> space.
>
> Think how much fuel is being wasted each day on airplanes, simply to support
> the extra weight required to carry the fuel itself. Think how dangerous
> airplanes are during relatively survivable impacts to the ground, primarily
> because they are gasoline bombs. I would be very interested to read about
> efforts to develop gas based engines for general aviation or commercial
> aircraft. I would appreciate any pointers to web sites or books.

Energy density. Look up the BTU/lb of different fuels, Gasoline and
Kerosine are
among the highest.

Light fuel tanks and high density fuel or
very heavy fuel tanks and low density fuel.

A college course on combustion theory will cover all this.

--
Harry Andreas
Engineering raconteur

[WDA]

"...Isn't there some way you could use two separate gases, which in their
separate state are inert, but combined together under high pressure, become
explosive?..."

Yes there is! Such fuels are termed hypergolic. One such combination was
used in the Walter RII-211 rocket motor of the World War II German Me 263
interceptor.

WDA
Former Fury Flyer!

end


"CHANGE username to westes" > wrote in
message ...
> Since taking up aviation as a hobby, I have wondered why gasoline, and
> similar oil-derived liquid fuels, have become the defacto standard for all
> forms of general aviation and commercial and military aircraft.
Comparing
> Jet fuel to something like natural gas, Jet fuel is four times as
expensive.
> Liquid fuels are extremely heavy, and certainly airplanes do not need
extra
> weight.
>
> This leads me to wonder why haven't engines been commercialized that can
> burn gas-based fuels? Is the only reason safety, because of the
> explosive nature of gas fuels like natural gas or hydrogen?
>
> Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure,
become
> explosive? Such a combination would not ignite if the airplane crashed
> (you could separate the gases into separate containers on each side of the
> airplane, at the wingtips), but in controlled injection into a high
pressure
> compartment could be made explosive in a controlled way, in a very limited
> space.
>
> Think how much fuel is being wasted each day on airplanes, simply to
support
> the extra weight required to carry the fuel itself. Think how dangerous
> airplanes are during relatively survivable impacts to the ground,
primarily
> because they are gasoline bombs. I would be very interested to read
about
> efforts to develop gas based engines for general aviation or commercial
> aircraft. I would appreciate any pointers to web sites or books.
>
> --
> Will
>
> NOTE: To reply, CHANGE the username to westes AT earthbroadcast.com
>
>

[B2431]

>From: "WDA"
>Date: 10/7/2003 4:04 PM Central Daylight Time
>Message-id: >
>
>"...Isn't there some way you could use two separate gases, which in their
>separate state are inert, but combined together under high pressure, become
>explosive?..."
>
>Yes there is! Such fuels are termed hypergolic. One such combination was
>used in the Walter RII-211 rocket motor of the World War II German Me 263
>interceptor.
>
>WDA
>Former Fury Flyer!
>

And used with varying degrees of success in the Me163 Komet.

Dan, U. S. Air Force, retired

[Keith Willshaw]

"WDA" > wrote in message
t...
> "...Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure,
become
> explosive?..."
>
> Yes there is! Such fuels are termed hypergolic. One such combination was
> used in the Walter RII-211 rocket motor of the World War II German Me 263
> interceptor.
>
> WDA
> Former Fury Flyer!
>
> end


I'd hardly call either C-stoff ( hydrogen peroxide) or T-stoff
(hydrazine hydrate, methyl alcohol and water) inert gases.

Keith

[Tank Fixer]

In article >,
says...
> Since taking up aviation as a hobby, I have wondered why gasoline, and
> similar oil-derived liquid fuels, have become the defacto standard for all
> forms of general aviation and commercial and military aircraft. Comparing
> Jet fuel to something like natural gas, Jet fuel is four times as expensive.
> Liquid fuels are extremely heavy, and certainly airplanes do not need extra
> weight.
>

Perhaps because in the early development of aircraft it was found to be a
sutible fuel ?




> This leads me to wonder why haven't engines been commercialized that can
> burn gas-based fuels? Is the only reason safety, because of the
> explosive nature of gas fuels like natural gas or hydrogen?
>

You will find any number fo ground vehicles that use LPG for fuel.


> Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure, become
> explosive? Such a combination would not ignite if the airplane crashed
> (you could separate the gases into separate containers on each side of the
> airplane, at the wingtips), but in controlled injection into a high pressure
> compartment could be made explosive in a controlled way, in a very limited
> space.
>
> Think how much fuel is being wasted each day on airplanes, simply to support
> the extra weight required to carry the fuel itself. Think how dangerous
> airplanes are during relatively survivable impacts to the ground, primarily
> because they are gasoline bombs. I would be very interested to read about
> efforts to develop gas based engines for general aviation or commercial
> aircraft. I would appreciate any pointers to web sites or books.
>

Think how safe airplanes would be if they were powered by coal fired steam
engines....

No wait, that won't work either.. coal dust = explosions..




--
When dealing with propaganda terminology one sometimes always speaks in
variable absolutes. This is not to be mistaken for an unbiased slant.

[[email protected]]

Tank Fixer > wrote:

>In article >,
says...
>> Since taking up aviation as a hobby, I have wondered why gasoline, and
>> similar oil-derived liquid fuels, have become the defacto standard for all
>> forms of general aviation and commercial and military aircraft. Comparing
>> Jet fuel to something like natural gas, Jet fuel is four times as expensive.
>> Liquid fuels are extremely heavy, and certainly airplanes do not need extra
>> weight.
>>
>
>Perhaps because in the early development of aircraft it was found to be a
>sutible fuel ?
>
>
>
>
>> This leads me to wonder why haven't engines been commercialized that can
>> burn gas-based fuels? Is the only reason safety, because of the
>> explosive nature of gas fuels like natural gas or hydrogen?
>>
>
>You will find any number fo ground vehicles that use LPG for fuel.
>
>
>> Isn't there some way you could use two separate gases, which in their
>> separate state are inert, but combined together under high pressure, become
>> explosive? Such a combination would not ignite if the airplane crashed
>> (you could separate the gases into separate containers on each side of the
>> airplane, at the wingtips), but in controlled injection into a high pressure
>> compartment could be made explosive in a controlled way, in a very limited
>> space.
>>
>> Think how much fuel is being wasted each day on airplanes, simply to support
>> the extra weight required to carry the fuel itself. Think how dangerous
>> airplanes are during relatively survivable impacts to the ground, primarily
>> because they are gasoline bombs. I would be very interested to read about
>> efforts to develop gas based engines for general aviation or commercial
>> aircraft. I would appreciate any pointers to web sites or books.
>>
>
>Think how safe airplanes would be if they were powered by coal fired steam
>engines....
>
>No wait, that won't work either.. coal dust = explosions..

I think that they've found that jet fuel (kerosene etc) has the
greatest energy pound for pound, it doesn't require special
handling (as LNG etc does) etc so it's the best and cheapest
available. You can bet yer butt that if another type were cheaper
then they'd be using that. A lot of good minds are involved in
the 'big bux' aviation world. They don't miss much.
--

-Gord.

[Tank Fixer]

In article >, "Gord Beaman"
) says...
> Tank Fixer > wrote:
>
> >In article >,
> says...
> >> Since taking up aviation as a hobby, I have wondered why gasoline, and
> >> similar oil-derived liquid fuels, have become the defacto standard for all
> >> forms of general aviation and commercial and military aircraft. Comparing
> >> Jet fuel to something like natural gas, Jet fuel is four times as expensive.
> >> Liquid fuels are extremely heavy, and certainly airplanes do not need extra
> >> weight.
> >>
> >
> >Perhaps because in the early development of aircraft it was found to be a
> >sutible fuel ?
> >
> >
> >
> >
> >> This leads me to wonder why haven't engines been commercialized that can
> >> burn gas-based fuels? Is the only reason safety, because of the
> >> explosive nature of gas fuels like natural gas or hydrogen?
> >>
> >
> >You will find any number fo ground vehicles that use LPG for fuel.
> >
> >
> >> Isn't there some way you could use two separate gases, which in their
> >> separate state are inert, but combined together under high pressure, become
> >> explosive? Such a combination would not ignite if the airplane crashed
> >> (you could separate the gases into separate containers on each side of the
> >> airplane, at the wingtips), but in controlled injection into a high pressure
> >> compartment could be made explosive in a controlled way, in a very limited
> >> space.
> >>
> >> Think how much fuel is being wasted each day on airplanes, simply to support
> >> the extra weight required to carry the fuel itself. Think how dangerous
> >> airplanes are during relatively survivable impacts to the ground, primarily
> >> because they are gasoline bombs. I would be very interested to read about
> >> efforts to develop gas based engines for general aviation or commercial
> >> aircraft. I would appreciate any pointers to web sites or books.
> >>
> >
> >Think how safe airplanes would be if they were powered by coal fired steam
> >engines....
> >
> >No wait, that won't work either.. coal dust = explosions..
>
> I think that they've found that jet fuel (kerosene etc) has the
> greatest energy pound for pound, it doesn't require special
> handling (as LNG etc does) etc so it's the best and cheapest
> available. You can bet yer butt that if another type were cheaper
> then they'd be using that. A lot of good minds are involved in
> the 'big bux' aviation world. They don't miss much.

Well aware of the extra handling and storage requirments for LPG.

The original poster is ignoring the history of aircraft development. They
used those fuel's that were available and cheap. I'd have to get into the
SG and BTU content of the various fuels but the current crop of jet fuels
have a good balance of stored energy to safety.



--
When dealing with propaganda terminology one sometimes always speaks in
variable absolutes. This is not to be mistaken for an unbiased slant.

[Bob Martin]

> Isn't there some way you could use two separate gases, which in their
> separate state are inert, but combined together under high pressure,
become
> explosive? Such a combination would not ignite if the airplane crashed
> (you could separate the gases into separate containers on each side of the
> airplane, at the wingtips), but in controlled injection into a high
pressure
> compartment could be made explosive in a controlled way, in a very limited
> space.

We've been using this for years in spacecraft. The Titan II that launched
Gemini capsules was powered by hypergolics. Mainly, though, these fuels are
used for in-orbit engines (Apollo, Soyuz, space shuttle, and Shenzhou all
use hypergolic propellants). The most common ones used are unsymmetrical
dimethyl hydrazine (UDMH) and nitrogen tetraoxide (NO4). These two
chemicals are EXTREMELY toxic.

Also, the Russian Proton rocket, and the launch vehicle the Chinese used to
launch their taikonaut, are powered by hypergolic fuels.