Inflight refueling

[TonyC]

well that was one of my questions...thanks

the other ones:

1 Doesn't that really f*ck with weight and ballance of both planes? One is getting heavier while the other is getting lighter...so wouldn't that also f*ck with airspeed, stall speed, power settings (you'd have to adjust to stay in the right place?), etc???

2 Doesn't the wake from that KC135 royally screw with the smaller jets???

Good stuff here guys...awesome.

He was being facetious about always being IMC on the boom.

From the perspective of both the tanker and the receiver - - CG has to be monitored and controlled. The tanker plans which tanks to offload the gas from, and has to keep CG within limits. The receiver plans which tanks to put the gas in to keep his CG within limits. The AR is usually planned at a constant airspeed. In order to maintain the constant airspeed, the tanker gradually reduces power, and the receiver has to gradually increase power. Sometimes, at higher altitudes, hotter temperatures, heavier weights, we would request the tanker leave the power set and allow the formation to accelerate - - little better throttle response at the higher airspeeds when we were close to the limits. Stall speeds -- yes, they changed, but we weren't anywhere close, so that was never a factor.


The wake turbulance from the KC-135 had a big effect on large airplanes. The vortices from the wingtips were directly in line with the wingtips of other -135s. Maintaining level flight just a few feet off centerline required a significant yoke input. Ironically, the phenomenon was not nearly as noticeable behind a KC-10 - - the wingtips were farther away. The same vortices would have been barely noticeable to a fighter.

 

[Eagleflip]

The same vortices would have been barely noticeable to a fighter.

Unless you were just a smidge high coming off the boom and returning to the wing. Had it happen one day when I was flying a three tanked Eagle and managed to catch the wake. Heard a couple of yaw warning beeps from the jet before it settled out--not a good thing when flying that configuration.

And yes, I was being facetious about always being IMC on the boom.

Unless you're doing an ocean crossing, that is!

Day VMC tankers were normally a blast. I was just recounting to one of my fellow pilots the joys of doing my first day A/R over northern Arizona. I could barely keep the tanker in view because I was looking at the massively beautiful terrain near Sedona.

 

[GasPasser]

perspective

While many of the aspects have been covered in answering the original question, one that was not mentioned was the effect that the position of the photo ship and the camera angle can have to the viewer of the photo. The photo ship can be below, above, behind, or beside the tanker, basiclly anywhere. The A/R formation could be straight and level, yet the photo could give the viewer the impression that they are in a turn, in a climb, or both. Great question, thanks for asking!

 

[Swede]

Tanking can be fun, or it can suck royally, depending upon weather, what tanker (KC10 vs KC135) turbulence, etc. Falling off the boom is always good for a laugh when it's not you, humiliating when it is. Usually good for a round of beers later. It is initially a totally unnatural act to make physical contact with another aircraft. The F15 had the worst possible boom inlet, behind the pilot and to the left, requiring liberal use of the rear-view mirror to help with positioning and boom extension once contacted. Once contact is made, a series of guide lights (like a fancy PAPI) helps you maintain an optimum position, although as other guys mentioned, positional cues relative to the tanker work best.

One of the BIG steps in a fighter-pilot's career is the dreaded 4-ship night tanker mission as part of a flight-lead upgrade. Often the hardest part of the mission is the rendezvous. The tanker flies a racetrack pattern, and as flight lead you need to create the intercept by usually calling for the tanker to turn, which he will do, hopefully rolling out in front of you. The altitudes are deconflicted until visual or good radar contact is made. A bad rendezvous will be with the flight in a multi-mile tailchase (more beers to buy), or worse, if the tanker rolls out BEHIND you on the track.

A quick story to end a long post, and probably one of the hairiest tanker stories I'm aware of. A good buddy was in Hawaii, enroute to Japan. A KC10 was making the run, and he recieved permission to fly with the tanker and thus make it in one leg. The distance required a large number of refuelings.

The fighter was an F15C. Well on his way, things went to $hit quickly. The first thing that went wrong was his inertial dumped, eliminating his INS and his radar as well. A partial electrical fault eliminated his TACAN. This guy had no way to navigate, no HF radio, no way to remain "tied" via radar to the KC10. Of course, at that point they hit a line of solid wx, requiring my bud to join on the tankers wing in hard and turbulent IMC. For FOUR HOURS. Going lost wingman almost guaranteed he'd end up in the water. Talk about motivation to maintain formation! Anyone who's flown close formation in IMC knows that it is challenging at the best of times due to spatial D. This guy's vestibular went bat-$hit. He felt that they were inverted, pointed straight down, etc, at various times over that hideous 4-hour span. He was totally strung-out after landing.

 

[dtfl]

In the 130 - the FE dumps the fuel into the mains because they take gas faster - but the CG isn't that critical - cargo is - and that's not moving. Your trim changes as you get heavier and your deck angle increases..and then comes the point where you do not have enough power to stay in so you toboggan - 300 fpm descent while tanking. I always enjoyed that ...tanker autopilot on, that is.

talking about Murphy's law - I can add a couple -
in combat your latches will always fail or your hyd will go out so you have to fly stiff boom....or your electrics dork up so you have to use manual disconnect procedures....those are what always happened to me. Never failed!! But combat=get it done.

 

[sandman2122]

The most fun (and work) you'll have!

Ahhhh yes, AR!

So there I was, just finished "First Pilot" school for the C-141 at Altus AFB, OK with @ 5 flights under my belt and they send me (and my buddy Brian W.) immediately to Air Refueling school.

It was probably one of the most demanding "stick & rudder" checkrides for me in the AF. Brand new to the Lizard, doing a night, IMC, heavy-weight rendezvous (sp) to a KC-135 - also from Altus. Talk about bull***t, we closed in on this guy to 1 mile, didn't see anything because it's night and we're IMC. Then my checkpilot tells the -135 to "turn on your strobes". We see a flash above and ahead of us and my EP says, "go get 'em". WTF! So there I go after his freakin strobes in the weather, until he materilized at the pre-contact position........pretty cool though. After getting my time on the boom autopilot on we got to do some autopilot off - which turned out to be vertical S alpha's +/- 500 fpm - niiiiiice. Left my seat pretty wet from sweat!

Awesome flying to get to do AR.

 

[MooseTrax]

I can assure you there is not a scarier job in the heavy training business than schoolhouse AR instructor.......well maybe assault landings too! And I completely understand what Swede is talking about being spatial D trying to get the gas in the weather, in the turn........It was fun (or should I say a challenge), but I don't miss it!

 

[dtfl]

Refueling - both of you blacked out and you on NVGs.

 

[MooseTrax]

WOW---even more fun! Take the field of view down to 40 degrees, no peripheral vision........can I get some weather and some turns please? No thanks!

 

[Swede]

I'm curious, those of you who have gassed via both boom (Af) and basket (Navy/Marines) which was more challenging?

The difference between the KC10 and the KC135 was striking. Besides having lighting like the Mother Ship from Close Encounters, the 10 had a very powerful boom. In other words, once contact was made, at least for a fighter, it felt like a giant had you in some kung-fu grip. The 135 had a puny boom, and if position wasn't maintained, you'd fall off pretty easily.

The guy operating the boom had a LOT to do with the tanking. Experienced boom operators would weild the boom like a big Zulu spear... you get within range and he stabs you. Other guys, well, we've all heard stuff like this:


BOOMER
"Forward 2..."
"Forward 2..."
"Forward 1..."
"Up 1..."
"Forward 1..."
"Down 1..."
"Back 1..."

RECIPIENT
"G.D. it, plug me NOW!!!!!!"

(THUNK) "Err, contact"

"Thanks A-hole"