Trying to find resources on tanker history

"Keith Willshaw" wrote in message
...

"Ian" wrote in message
...




Is it still the case that the USN uses the trailing drogue (as the
RAF/RN
do), with the USAF using the tanker to steer the probe? If so, why the
different approaches?



The flying boom method has a higher transfer rate but probe
and drogue can be fitted to buddy tankers.

Keith

Maybe a bit simplistic but couldn't they equal the transfer rates by just
increasing the bore of the drogue feed pipe? It all ends up in the same fuel
system (on the refuelling aircraft) so it can't be a pressure constraint?

"Ian" wrote in message
...



Maybe a bit simplistic but couldn't they equal the transfer rates by just
increasing the bore of the drogue feed pipe? It all ends up in the same
fuel
system (on the refuelling aircraft) so it can't be a pressure constraint?



That means increasing the bore of a longer length of pipe
than on a flying boom. I suspect there are weight restraints
at work here.

Keith




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Keith Willshaw wrote:

"Ian" wrote in message
...



Maybe a bit simplistic but couldn't they equal the transfer rates by just
increasing the bore of the drogue feed pipe? It all ends up in the same
fuel
system (on the refuelling aircraft) so it can't be a pressure constraint?



That means increasing the bore of a longer length of pipe
than on a flying boom. I suspect there are weight restraints
at work here.

And size (hose takes up space, after all), and drag. More importantly, there are
limits on the size at the other end. While large a/c can carry around a large
diameter fixed probe with little effect on performance, fighters and attack a/c don't
have that option. So, for instance, on their Victor tankers the RAF used Mk. 20 wing
pods with smaller diameter hose/drogues (and lower flow rates) to refuel
fighter/attack a/c, and a centerline Mk. 17 HDU of greater diameter hose/drogue to
refuel bombers/transports (which have larger diameter probes than fighter/attack
aircraft, so can accept higher transfer rates, although still not as high as a boom).
A fighter just can't be carrying around such a massive piece of hardware all the time,
especially if it's fixed external (there wouldn't be enough room to house it
internally on a fighter, and no one seems to have tried a bomber-sized extendible
probe).

A boom receptacle, OTOH, is theoretically only limited in diameter by the fuel flow
rates that the a/c's internal fuel piping is designed to deal with; since the flow
rate in A/B is quite high, and since none of this is adding weight/drag outside the
airframe, transfer rates can be much higher with little/no weight penalty on the
receiver. The tanker is paying the weight/drag penalty of the boom, but it's a lot
larger and can afford it.

Guy

Guy Alcala wrote:
A boom receptacle, OTOH, is theoretically only limited in diameter by the fuel flow
rates that the a/c's internal fuel piping is designed to deal with; since the flow
rate in A/B is quite high, and since none of this is adding weight/drag outside the
airframe, transfer rates can be much higher with little/no weight penalty on the
receiver. The tanker is paying the weight/drag penalty of the boom, but it's a lot
larger and can afford it.

And then you've got three pilots.

One pilot for each aircraft and then somebody in the back of the tanker
to fly the boom.

-HJC

"Henry J Cobb" wrote in message
...
Guy Alcala wrote:
A boom receptacle, OTOH, is theoretically only limited in diameter by
the fuel flow
rates that the a/c's internal fuel piping is designed to deal with;
since the flow
rate in A/B is quite high, and since none of this is adding weight/drag
outside the
airframe, transfer rates can be much higher with little/no weight
penalty on the
receiver. The tanker is paying the weight/drag penalty of the boom, but
it's a lot
larger and can afford it.

And then you've got three pilots.

One pilot for each aircraft and then somebody in the back of the tanker
to fly the boom.

The boom operator is neither trained nor paid as a pilot, so your point
would be...?

Brooks

-HJC

Kevin Brooks wrote:
"Henry J Cobb" wrote in message
...
And then you've got three pilots.

One pilot for each aircraft and then somebody in the back of the tanker
to fly the boom.

The boom operator is neither trained nor paid as a pilot, so your point
would be...?

"Fly the boom" is a common phrase in the USAF.

http://www.afmc.wpafb.af.mil/HQ-AFMC...eb/0226-03.htm

You need three people adjusting airfoils to make boom refueling work.

That's one more person than is needed for a probe and drogue refueling.

Heck, you could make an unmanned tanker for probe and drogue refueling.

-HJC

"Henry J Cobb" wrote in message
...
Guy Alcala wrote:
After that the USAF decided to go
over completely to the boom/receptacle method, as their tankers would
(presumably) always have airbases to operate from, just as their
fighters and
bombers would. The boom gives better transfer rates and seems to be
more
reliable and easier to tank from, but it does limit the types of a/c
that can
be tankers, and it requires a lot more money and work to convert.

Will the F-35B be the first USAF aircraft since then to be built with
just a probe?

Clearly USAF helicopters have been built with "just a probe".
Outside of the rotory wings I can't think of any USAF probe
refuelers during the last 30 some years.

On Wed, 2 Jun 2004 01:00:49 -0400, "John Keeney"
wrote:


"Henry J Cobb" wrote in message
...
Guy Alcala wrote:
After that the USAF decided to go
over completely to the boom/receptacle method, as their tankers would
(presumably) always have airbases to operate from, just as their
fighters and
bombers would. The boom gives better transfer rates and seems to be
more
reliable and easier to tank from, but it does limit the types of a/c
that can
be tankers, and it requires a lot more money and work to convert.

Will the F-35B be the first USAF aircraft since then to be built with
just a probe?

Clearly USAF helicopters have been built with "just a probe".
Outside of the rotory wings I can't think of any USAF probe
refuelers during the last 30 some years.

A-7D?

John Keeney wrote:
Clearly USAF helicopters have been built with "just a probe".
Outside of the rotory wings I can't think of any USAF probe
refuelers during the last 30 some years.

How many helicopter capable tankers does the USAF have?

Or do they have to call in the Marines? ;-)

-HJC

On Tue, 01 Jun 2004 19:17:23 -0700, Henry J Cobb wrote:

One pilot for each aircraft and then somebody in the back of the tanker
to fly the boom.

The boom handler is a pilot? Why?

There used to be a joke about flying up dead-end canyons: don't do it
unless you've learned how to fly a plane backwards. Presumably a boom
operator could do just that.

all the best -- Dan Ford
email: (put Cubdriver in subject line)

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