A question concerning aerial refuelling.

Yes but if they had made it to China they would have gotten home. China was at war with the Japs too so they were allied with the allies.

DerAdlerIstGelandet said:

Yes but if they had made it to China they would have gotten home. China was at war with the Japs too so they were allied with the allies.

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The Dolittle B-25s were always supposed to go to the Chinese/Flying Tiger Air Force. for use in China for use against the Japanese. There never was a thought of returning to the carriers.

The Droug/Boom issues are as follows:

1. The Speed difference of aircraft. Planes like the B-47 were atnear thier stall speeds while the KB-29/KC-97s were at absolute top speed, very hard on everything. Compounding this is the weight transfer complicates the situation. Air Force Transfers are frequently over 10,000lbs, Navy transfers are closer to 5,000lbs normaly.
2. Relative maneuverability is severly limited at/near stall speed while the boom was/is flyable, limiting the need to go after a droug.
3. Fuel flow. I think the boom flows 4/5 times the fuel per min.
4. Stability - the boom acts like a shock absorber and in some cases has been used to Tow aircraft that couldn't get fuel to conserve what they had for landing. This happened several times in the Vietnam war.

The Navy has other priorities namely weight and compact size. Naval aircraft are of more similar performance capabilities and some droug systems can be switched to different aircraft in a pinch.

wmaxt

wmaxt said:

DerAdlerIstGelandet said:

Yes but if they had made it to China they would have gotten home. China was at war with the Japs too so they were allied with the allies.

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The Dolittle B-25s were always supposed to go to the Chinese/Flying Tiger Air Force. for use in China for use against the Japanese. There never was a thought of returning to the carriers.

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I never said they were supposed to go to the Carriers. I said if they had made it to China they would have made it home, implying the crews would have made it home.

The difference between the drogue method and the boom method may have been the amount of fuel transferred and the mission. The boom was actually very maneuverable: it could be moved by the KC 135 "Casey" up to 40 degrees down, 20 degrees up, and 10 degrees either side. It was 33 feet long and had another 12 feet that could telescope out and into the four inch fuel receptacle. Refueling of 120,000 pounds of fuel would usually take about 20 minutes for a B-52. It was called the flying boom because of the small wings on either side controlled by the boom operator.
And the reason they called the refueling operator "Casey" was because he lowered the boom.

Hey, here's one I can help answer (for a change)

KC-10 crew chief here... with an awful lot of time having to fix damned booms and drogues.

First, keep in mind mission drives the gear.

Some of you have touched on a little of the why... but wait! There's more!

For the AF that has a lot of heavies to refuel (as well as puddle jumpers) it needs to move a lot of fuel fast and the boom does that. Also, must consider that the boom is far more stabile in flight. (while I don't recall the fuel flow rates exactly, I recall that a KC-10 can transfer as much fuel in 5 minutes as a gas station pump (for autos) can in 24 hours... or something like that, don't quote me exactly)

The Navy for the most part doesn't have to move a lot of fuel at a time as most of the acft are small and also there's the whole landing on a carrier thingie which helps to keep the acft size to a minimum.

The real reason is HELICOPTERS! It's awfully hard to fly a boom down between spinning rotor blades. Look at sea stallions or even Jolly Green Giants with the big probes that jut out in front to avoid the blades. The drogue just has to come in on the horizontal (rather than a diagonal for the boom). So, for standardization, Navy has probes on all it's acft.

Also, the 135's and KC-10's fly too fast for heli's... so even though they have drogues for navy, they don't do heli's.

Trivia: On KC-10's, if A-10's are in the mission profile, they must use KC-10's that are not modded with the drogue pods on the wings. This is because of drag and lift restrictions... the KC -10 cannot fly slow enough for the A-10 to keep up when the tanker has the drogue pods installed.

And remember: no one kicks ass without tanker gas! LOL

Found this for KC-10's: During boom refueling operations, fuel is transferred to the receiver at a maximum rate of 1,100 gallons (4,180 liters) per minute; the hose and drogue refueling maximum rate is 470 gallons (1,786 liters) per minute.

Found here: KC-10 Extender > U.S. Air Force > Fact Sheet Display

Might help a bit. Boom is almost 4 times faster than the drogue.

Robert Porter said:

Found this for KC-10's: During boom refueling operations, fuel is transferred to the receiver at a maximum rate of 1,100 gallons (4,180 liters) per minute; the hose and drogue refueling maximum rate is 470 gallons (1,786 liters) per minute.

Found here: KC-10 Extender > U.S. Air Force > Fact Sheet Display

Might help a bit. Boom is almost 4 times faster than the drogue.

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From memory the HP Victor bomber modified as a tanker could transfer 1200lbs a minute for the wing tip pods and 8000 lbs for the central unit. Don't quote me on exact numbers but there were high flow probe and Droge units for heavy aircraft. Russian Bears refuel this way.

There were loads of methods of in-flight refueling proposed by people of all sorts in the 1920's and 1930's. The problem is they weren't always designs that would be reliable and practical for combat.

By 1934 there was a guy named Alan Cobham who was working on a looped-hose with grapnel line that he had in use by 1938 or 1939: It required multiple-man crew, but was actually used on at least one flying-bloat aircraft. The idea was to takeoff light, then refuel in mid-air with the hope of extending range 50%.

In 1942, the idea was tested by the USAAF and rejected. There were proposals that entailed sliding a drop-tank onto the wing of a P-38, that seemed to be rejected.

When the Air Force became independent: It was decided to develop an in-flight refueling system. The looped-hose & grapnel line was used first, but it's requirement for multi-man crews ruled out fighter-escorts. So eventually they went with what we now call the probe and drogue. When the US Navy started to develop nuclear-strike, this was implemented as well.

It worked fine for aircraft of fighter size up to even some jet-bombers, but for larger aircraft, it was a problem because of slow refueling times as mentioned. This gave way to the flying-boom, but it was only used by SAC at first (I'm not sure if MAC was using it at first). Starting in the late 1960's it was used by all USAF branches.

Zipper730 said:

but was actually used on at least one flying-bloat aircraft.

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There was one "bloat" (S.30 G-AFCU Cabot) that was refueled in flight from a Handley Page Harrow in '39.
900 gallons took 15 minutes to transfer.
Here's the mechanism inside the Harrow that controlled the refueling hose...

Nonskimmer said:

I've often wondered, and have never really found a satisfactory answer, as to why the US Air Force uses the exact opposite refuelling probe arrangement on it's aircraft from the Navy and Marine Corps.

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DerAdlerIstGelandet said:

To be honest I really dont know, but I would say it is because in tradition the US military can not agree on anything whether it is uniforms, equipment or aerial refueling.

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That would be my guess too for the reversed connections.

Look at the Technical Orders (manuals) as another prime example. In WW2 the military started to have AN Technical Orders where the same manual was used by both services for aircraft and other material used by both services. That is why many of the wartime TO's have a number prefixed with AN for Army/Navy.

About the time the USAF became separate that fell apart -- even before the war was over the brass felt that fighting over document numbering systems was as important as fighting the enemy. They remind me of the seagulls in Finding Nemo.

Seventy years later they still have the stupidity that all three services use the identical manual but each service has its own TO number and numbering system.

Military Intelligence at its finest OR a pack of spoiled three year olds, take your pick.

Either way maintaining three numbering systems costs the taxpayer three times what a single system would cost.

AND the brass behind this like to pretend they are responsible adults!

Graeme said:

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Hahahahaha! Sorry about that!

There was one "bloat" (S.30 G-AFCU Cabot) that was refueled in flight from a Handley Page Harrow in '39.
900 gallons took 15 minutes to transfer.

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60 gallons a minute...

MiTasol said:

Look at the Technical Orders (manuals) as another prime example. In WW2 the military started to have AN Technical Orders where the same manual was used by both services for aircraft and other material used by both services. That is why many of the wartime TO's have a number prefixed with AN for Army/Navy.

About the time the USAF became separate that fell apart -- even before the war was over the brass felt that fighting over document numbering systems was as important as fighting the enemy.

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Why?

MiTasol said:

Either way maintaining three numbering systems costs the taxpayer three times what a single system would cost.

AND the brass behind this like to pretend they are responsible adults!

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They are responsible for maintaining their own positions/jobs for themselves and future generations of officers in their respective services.