Originally Posted by Tdog02
Astro, what is the difference between Air Force refueling and Navy refueling? Is it preference from the branch of the service or is there some benefit of one over the other? Does it have to do with the size of aircraft and typical fuel load? The AF way seems complicated but they are pushing a lot of fuel from a large plane. Just something to occupy the brain.
USAF uses a boom system. USN uses a drogue system.
Air Force Tankers, with their booms, were designed and built in the early 1950s to get strategic bombers to their distant targets. the KC-97 was the first, the KC-135 next, and KC-10 after that. Since the tankers were already built and flying, subsequent USAF fighters were simply built with the boom receptacle. Early 1950s USAF fighters, like the F-100 still had probes for the drogue system.
But the Boom requires a big tanker, like the KC-135 (707).
The Navy needs to be able to tank "organically" - that is, using airplanes launched from a carrier. So, A-3, A-6, A-7, S-3, and now, F/A-18 have all been equipped with the "buddy store" D-705 pod that has a self-contained drogue.
Tanking during a night (or even day) recovery is an essential safety element. Airplanes run low on gas because they miss the first or second landing attempt and they need to get refueled to stay in the air. This is essential for "Blue water operations", i.e. operations with no divert. The fuel at max landing weight in a combat-loaded F/A-18C model is often 3,000# or so. That's three landing attempts and then flame-out. About 25-30 minutes of total fuel. So, one look at the deck, perhaps two in the day time, and it's off to the tanker, circling overhead and watching the low state aircraft.
Being the tanker pilot in the "hawk', or watching the low state aircraft, requires aggressive maneuvering so that if that aircraft bolters (misses the wires on a landing attempt) the tanker is about 1/2 mile ahead and on the right side of the low state aircraft, making for an easy rendezvous in an orbiting left hand turn overhead the ship.
So, can't fit a boom on a carrier, but need to be able to tank from the carrier = probe and drogue.
When we operate jointly, the USAF fits a drogue on the end of the boom of the KC-135 to tank Navy airplanes. Some KC-135s (and some civilian contract tankers) have wing refueling pods, which are basically the D-705 pod mounted on a wing hard point, enabling the tanker to refuel both drogue and boom airplanes. The KC-10 had a built in drogue, which allowed it to launch with the ability to swing both ways in the air.
The boom is large, heavy, and complex. It's not just the USN that uses the drogue system. Every NATO Ally nation uses the drogue. Look at the British V-series bombers, big bombers with a probe on them. Current NATO fighters, bombers, transport and patrol aircraft, like the Nimrod all use the drogue. Even the brand new A-400M military transport from Airbus has, yep, a probe on the front.
Makes it easy for the USN to work in an Allied environment. We can tank (and I have) off British or French tankers without worrying, "is this a drogue? or a boom?".
https://www.cobham.com/mission-syst...ng-pods/31-300-buddy-store-datasheet/docview/
en.wikipedia.org
en.wikipedia.org