bjohnson@athena.mit.edu (Brett W Johnson) (11/14/90)
From: bjohnson@athena.mit.edu (Brett W Johnson) I have a question on air-to-air refueling. I read recently that modern jets/tankers have electronics (ie radar) designed to maintain proper seperation of the planes and nozzle alignment. Can AA refueling be accomplished w/o this? Using only the skill of the pilots & boom operator? If so, why wasn't this technique used in WW2? Or was it? -- -Brett These opinions are my own and bjohnson@athena.mit.edu do not neccessarily reflect bjohnson@micro.ll.mit.edu those of my employer or MIT.
james@castle.ed.ac.uk (J Gillespie) (11/15/90)
From: J Gillespie <james@castle.ed.ac.uk> bjohnson@athena.mit.edu (Brett W Johnson) writes: >From: bjohnson@athena.mit.edu (Brett W Johnson) >I have a question on air-to-air refueling. I read recently that >modern jets/tankers have electronics (ie radar) designed to maintain >proper seperation of the planes and nozzle alignment. Can AA refueling >be accomplished w/o this? Using only the skill of the pilots & boom >operator? >If so, why wasn't this technique used in WW2? Or was it? I haven't recently discussed this in detail with him, but my father is a Nimrod pilot in the RAF, and as such carries out refueling exercises on a regular basis to maintain currency. The last time I talked to him about this, he said that the only guidance pilots have is special markings on the tanker; none of our tankers (Victor, C-130, TriStar) were purpose built as such, and all use unguided fuel hoses, i.e. a long flexible hose with a basket on the end. To clarify the system, the tanker drags a hose with a basket on the end, and the tanking aircraft has a probe somewhere near the nose, rather like a CH-53. The tanker flies on autopilot, and the tankee (?) flies manually. To make things more interesting, when C-130 Hercules are used as tankers, their top speed is slower than a Nimrod's slowest speed, and so refueling has to be carried out during a descending maneuver. A note on the hose and basket: separation is fairly critical, and any changes must be smooth - yo yo-ing can set up waves which break either the basket or the refueling probe. The same effect can be obtained by too great a docking speed. Hope this helps. -- __ /~~~~~~~~\ / / @ @ \ "Happiness is being famous for your financial / / /\/\ / < \ ability to indulge in every form of excess" \_/_/_/___/_/ \________/ \__________________________________________-- Calvin
henry@zoo.toronto.edu (Henry Spencer) (11/15/90)
From: henry@zoo.toronto.edu (Henry Spencer) >From: bjohnson@athena.mit.edu (Brett W Johnson) >I have a question on air-to-air refueling. I read recently that >modern jets/tankers have electronics (ie radar) designed to maintain >proper seperation of the planes and nozzle alignment. Can AA refueling >be accomplished w/o this? Using only the skill of the pilots & boom >operator? Yes. In fact, most of the tankers in service don't have the fancy electronics. The USAF's older tankers are manually operated, as are all non-USAF tankers. (Basically only the USAF uses flying-boom refuelling; everyone else, including the USN, uses probe-and-drogue refuelling with a flexible hose connecting the two aircraft.) >If so, why wasn't this technique used in WW2? Or was it? For some reason it took a long time for the idea to be taken seriously. Although there were experiments and stunts earlier, the technique wasn't really operational until the 1950s. -- "I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology "Not to worry." | henry@zoo.toronto.edu utzoo!henry
ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) (11/16/90)
From: ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib)
About mid-air refueling:
>>If so, why wasn't this technique used in WW2? Or was it?
Perhaps because of two reasons?
1) Kerosene is less dangerous than gasoline
2) Propellors are potentially dangerous
-------------------------------------------------------------------------------
Iskandar Taib | The only thing worse than Peach ala
Internet: NTAIB@AQUA.UCS.INDIANA.EDU | Frog is Frog ala Peach
Bitnet: NTAIB@IUBACS !shafer@skipper.dfrf.nasa.gov (Mary Shafer) (11/16/90)
From: Mary Shafer <shafer@skipper.dfrf.nasa.gov>
Brett W Johnson (bjohnson@athena.mit.edu) writes:
I have a question on air-to-air refueling. I read recently that
modern jets/tankers have electronics (ie radar) designed to maintain
proper seperation of the planes and nozzle alignment. Can AA refueling
be accomplished w/o this? Using only the skill of the pilots & boom
operator?
First a quick bit of information--the USAF uses boom/receptacle
refuelling and everyone else uses probe/drogue refuelling. This is
because USAF's big bombers can't feasibly be refuelled with
probe/drogue.
Yes, air-to-air refuelling is accomplished by pilots and boomers
and has been since the 50s, when it was developed.
If so, why wasn't this technique used in WW2? Or was it?
Because it wasn't until jets came around that refuelling became
imperative. Range extension in WW II fighters came from drop tanks.
--
Mary Shafer shafer@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer
NASA Ames Dryden Flight Research Facility, Edwards, CA
Of course I don't speak for NASA
"A MiG at your six is better than no MiG at all"--Unknown US fighter pilothenry@zoo.toronto.edu (Henry Spencer) (11/19/90)
From: henry@zoo.toronto.edu (Henry Spencer) >From: Mary Shafer <shafer@skipper.dfrf.nasa.gov> >because USAF's big bombers can't feasibly be refuelled with >probe/drogue. Can you substantiate this, Mary? The RAF routinely refuelled heavy bombers with probe/drogue. The p/d fuel flow rate is lower than f-b with current hardware, but one could always use a fatter hose... I believe the USAF did cite difficulties with p/d as their original reason for going with f-b, but they were mostly minor problems likely to yield to modest engineering effort. (Which is exactly what happened when the effort was invested.) There wasn't anything fundamentally wrong with p/d that I know of. -- "I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology "Not to worry." | henry@zoo.toronto.edu utzoo!henry
ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) (11/20/90)
From: ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) > If so, why wasn't this technique used in WW2? Or was it? >Because it wasn't until jets came around that refuelling became >imperative. Range extension in WW II fighters came from drop tanks. I suppose so.. but I'll bet the 8th air force desparately wanted added range beyond what drop tanks provided its P-47s and P-38s early in the bomber offensive against Ger- many! The germans would wait just beyond the range of the fighter escort. The P-51 solved this problem. ------------------------------------------------------------------------------- Iskandar Taib | The only thing worse than Peach ala Internet: NTAIB@AQUA.UCS.INDIANA.EDU | Frog is Frog ala Peach Bitnet: NTAIB@IUBACS !
shafer@skipper.dfrf.nasa.gov (Mary Shafer) (11/20/90)
From: Mary Shafer <shafer@skipper.dfrf.nasa.gov> Henry Spencer (henry@zoo.toronto.edu) writes: >>From: Mary Shafer <shafer@skipper.dfrf.nasa.gov> >>because USAF's big bombers can't feasibly be refuelled with >>probe/drogue. >Can you substantiate this, Mary? The RAF routinely refuelled heavy bombers >with probe/drogue. The p/d fuel flow rate is lower than f-b with current >hardware, but one could always use a fatter hose... It would have been better had I written "... big bombers _couldn't_ be refuelled ...." since I was referring to the original conditions. >I believe the USAF did cite difficulties with p/d as their original reason >for going with f-b, but they were mostly minor problems likely to yield >to modest engineering effort. (Which is exactly what happened when the >effort was invested.) There wasn't anything fundamentally wrong with p/d >that I know of. There's nothing wrong with probe-drogue refuelling, but once you've decided to use boom/receptacle and all your receiver aircraft have receptacles, not probes, the question becomes moot. I personally think that probe/drogue refuelling is superior, even if you ignore the compatibility issues. There is a small advantage in having the high-gain part of the task rest with someone other than the low-on-fuel pilot, but not enough to make any real difference. Also remember that the only thing the USAF and USN have ever agreed on is that the Army shouldn't have fixed-wing aircraft. -- Mary Shafer shafer@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA "A MiG at your six is better than no MiG at all"--Unknown US fighter pilot
shafer@skipper.dfrf.nasa.gov (Mary Shafer) (11/22/90)
From: Mary Shafer <shafer@skipper.dfrf.nasa.gov>
Just to add a little history to this discussion, Sir Alan Cobham was
working on aerial refuelling in the early 30s. (Or so says Nevil Shute
Norway, in "Round the Bend").
--
Mary Shafer shafer@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer
NASA Ames Dryden Flight Research Facility, Edwards, CA
Of course I don't speak for NASA
"A MiG at your six is better than no MiG at all"--Unknown US fighter pilotjwm@wdl76.wdl.fac.com (Jon W Meyer) (11/22/90)
From: jwm@wdl76.wdl.fac.com (Jon W Meyer) shafer@skipper.dfrf.nasa.gov (Mary Shafer) writes: >Henry Spencer (henry@zoo.toronto.edu) writes: >>I believe the USAF did cite difficulties with p/d as their original reason >>for going with f-b, but they were mostly minor problems likely to yield >There's nothing wrong with probe-drogue refuelling, but once you've >decided to use boom/receptacle and all your receiver aircraft have >receptacles, not probes, the question becomes moot. Just a nit, but the USAF uses both flying boom and probe & drouge refueling. While most fixed wing USAF aircraft (the air refuelable ones, that is) are set up for the boom, helecopters are refueled from HC-130s (that's right, HC not KC) using probe and drogue. There seems to be some incompatibility between the booms and the spinning things above the helecopters' fuselages. :-) >Also remember that the only thing the USAF and USN have ever agreed on >is that the Army shouldn't have fixed-wing aircraft. I don't know about that. I think they both agree that trying to land fighters on a piece of driftwood bobing along in the middle of the ocean is something only a lunatic, grasnted, a highly skilled lunatic, would attempt. :-) Jon ____________________________________________________________________________ Jon W. Meyer | "I'd travel 10,000 miles to smoke a camel" | Caption from the (unofficial) desert shield tee-shirt. | | "If, when the battle's over, your infantry does not love you, | you are a poor artillery man."
fiddler@Eng.Sun.COM (Steve Hix) (11/22/90)
From: fiddler@Eng.Sun.COM (Steve Hix) > From: ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) > > I suppose so.. but I'll bet the 8th air force desparately > wanted added range beyond what drop tanks provided its > P-47s and P-38s early in the bomber offensive against Ger- > many! The germans would wait just beyond the range of the > fighter escort. The P-51 solved this problem. Both P-47s and P-51s, with drop tanks, had the range to escort bombers all the way in and back to German targets. The later P-47s with the bubble canopy were in perpetual contest with the P-51D as highest-scoring American fighter type. The P-38 with drop tanks had the range, but were not considered competitive against later Luftwaffe fighters. Most P-38s were assigned to North Africa and Italy anyway. It's not that the P-38J-LO wasn't all that good...it's mostly that earlier variants couldn't turn with the Germans, and being as big as they were, could be spotted from quite a bit further out than single-engined fighters. This last was a real disadvantage. -- ------------ The only drawback with morning is that it comes at such an inconvenient time of day. ------------
ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) (11/27/90)
From: ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) *>Both P-47s and P-51s, with drop tanks, had the range to escort *>bombers all the way in and back to German targets. The later *>P-47s with the bubble canopy were in perpetual contest with the *>P-51D as highest-scoring American fighter type. *>The P-38 with drop tanks had the range, but were not considered *>competitive against later Luftwaffe fighters. Most P-38s were *>assigned to North Africa and Italy anyway. *>It's not that the P-38J-LO wasn't all that good...it's mostly *>that earlier variants couldn't turn with the Germans, and being *>as big as they were, could be spotted from quite a bit further *>out than single-engined fighters. This last was a real disadvantage. Well, actually, earlier in the war, the P-47s and P-38s didn't have the range to escort bom- bers all the way into Germany. The later model Jugs were probably a little better as far as range was concerned, but accounts of the frus- trations felt by allied fighter pilots watching as German fighters waited just beyond their range are numerous. Of course, this does not begin to compare with how the bomber crews felt. (!) The P-38 eventually did turn into a fantastic fighter when used properly. It could (in some situations) turn inside german fighters by using its maneuvering flaps - a button, when depressed, would lower the flaps to a pre-de- termined setting. It was mostly deficient in roll rate. The biggest problems early on were reliability (those Allisons kept blowing up and were a real pain to repair) and the lack of the compressibility flap fitted to later models - the airplane would, in a dive, sudden- ly lock its controls solid and tuck its nose under, often tearing the wings off. Not very nice when German pilots went into a dive to escape - you couldn't follow one in an early model Lightning. (The Jug, on the other hand, could dive faster than anything else and scored heavily on German pilots attempting to flee.) In the Pacific and North Africa/Italy the P-38s really shone. Against the Japanese navy fighters the tactic was to attack in a shallow dive, then escape in a climb, as the Zeroes could turn inside any fighter the allies had, but could not catch a Lightning in a climb (very few airplanes could). As far as high visibility was concerned, the odd configuration of the Lightning was either a blessing or a disadvan- tage. It gave ones' away at long range. If it was to enemy fighters, it was a disadvantage, if to friendly bomber crews, an advantage. The F-15 has been said to have a similar problem. Its size makes it visible from miles away, earning it the nickname "Twin Tailed Tennis Court". On a side (very unrelated, actually) note.. The British decided, at one time, to teach the Zero pilots a lesson by sending over, from Eu- rope, a crack Spitfire squadron to Northern Australia. The Spitfire pilots decided to use turning tactics against the Zeroes and ended up losing 17 pilots out of 27 in two raids. This was mentioned in passing in Martin Caidin's book about the early war in the Pacific (I forget the title). Does anyone know more about this incident? Which squadron? What mark of Spitfire were they flying? When exactly did this take place? ------------------------------------------------------------------------------- Iskandar Taib | The only thing worse than Peach ala Internet: NTAIB@AQUA.UCS.INDIANA.EDU | Frog is Frog ala Peach Bitnet: NTAIB@IUBACS !
bsmart@uunet.UU.NET (Bob Smart) (12/03/90)
From: vrdxhq!vrdxhq.verdix.com!bsmart@uunet.UU.NET (Bob Smart) in article <1990Nov19.003026.10700@cbnews.att.com>, henry@zoo.toronto.edu (Henry Spencer) says: > Approved: military@att.att.com > > > > From: henry@zoo.toronto.edu (Henry Spencer) >>From: Mary Shafer <shafer@skipper.dfrf.nasa.gov> >>because USAF's big bombers can't feasibly be refuelled with >>probe/drogue. > > Can you substantiate this, Mary? The RAF routinely refuelled heavy bombers > with probe/drogue. The p/d fuel flow rate is lower than f-b with current > hardware, but one could always use a fatter hose... > -- > "I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology > "Not to worry." | henry@zoo.toronto.edu utzoo!henry The flow rate is one of the reasons ( especially back in the fiftys when the decision was made) Another was the reliability of making hookups in a minimum of time. I have been told by boomers on KC-10's that especially in rough weather hookups are faster and more reliable with the boom. Tactical Air Command used to use p-d until the early 60's ( F-100, F-104, etc) in fact I think the early F-105s had both a probe and a recepticle for the boom but I am not 100% sure, This is based on some info I saw on the F-105B model I saw over 10 years ago and can't remember exactly where. Some old fighter pilots in my old unit who had flown F-100s across the Atlantic on Deployments. He said they always had diverts who could not make the hookups with the tanker and had to divert back to the US or to the Azores which was available for 'emergencies only' He said that with booms He could only remember a couple diverts in many deployments of F-4, A-7, and F-15 aircraft ( He did give credit to the increased range that cut the number of 'tanker hits' at least in half, but also said that due to the mindset that they would be able to connect no matter what they were willing to let the tanks get lower before topping off). I think that today both systems have proven reliable enough to depend on and the decision is now based on other grounds. 1) P-D systems are cheaper, portable buddy pack systems even enable fighters to act as tankers. ( I remember seeing a photo of an external tank with a probe on the nose that enabled non-probe equiped aircraft to do IFR. 2) Lower stresses placed on airframe of reciever by P-D. ( There is some pretty strong re-enforcment around the boom recepticle on aircraft I have worked on or been able to examine. 3) Easier to add a probe as an after thought whereas fewer aircraft have had recepticles added. Did everyone know that there is a variation of boom refueling. Some C-135s ( mainly airborne command post, radio relay, etc type aircraft) are equiped for reverse flow refueling. In this case the boom equiped aircraft is the reciever. I was told that it was much easier to do this and use a B-52 as a middleman/tanker than to add a recepticle to many of the C-135 types. I do know that some C-135 class airframes were equiped with recepticles. Bob Smart (bsmart@verdix.com) ex B32678 AFSC ( Comm,Nav,ECM flightline)
wul@sco.COM (Wu Liu) (12/05/90)
From: Wu Liu <wul@sco.COM> Note: Comments about the respective combat ranges for P-38, P-47, and P-51 fighters deleted. /--ntaib@silver.ucs.indiana.edu (Nur Iskandar Taib) said... | On a side (very unrelated, actually) note.. | | The British decided, at one time, to teach the | Zero pilots a lesson by sending over, from Eu- | rope, a crack Spitfire squadron to Northern | Australia. The Spitfire pilots decided to use | turning tactics against the Zeroes and ended | up losing 17 pilots out of 27 in two raids. | This was mentioned in passing in Martin Caidin's | book about the early war in the Pacific (I | forget the title). Does anyone know more about | this incident? Which squadron? What mark of | Spitfire were they flying? When exactly did this | take place? \-- The book you're referring to is, I think, "The Ragged, Rugged Warriors" by Martin Caidin. As I recall, the aerial defense of Rangoon, Burma was handled by a squadron of RAF Hurricans (not Spitfires) and the Flying Tigers (Tex Hill's?). The Tigers stuck primarily to Claire Chennault's tactic of hitting and running in their P-40s, while the RAF pilots, veterans of the Battle of Britain, tried to turn with the Japanese. The British were probably flying Hurricane Mk IIs, the time frame being early- to mid-1942. I'd check the book, but (unfortunately) it's several states away at the moment... -- Wu Liu -- Member, Technical Staff The Santa Cruz Operation, Inc. UUCP: ...!uunet!sco!wul 400 Encinal St. Internet: wul@sco.COM Santa Cruz, CA 95061