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Air to Air refueling.Would you contemplate it?

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Air to Air refueling.Would you contemplate it?

Old 23rd Jul 2005, 15:15
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Air to Air refueling.Would you contemplate it?

Air to Air refueling.Valid in civilian aircraft or not?

Noticed this article in todays Times.From what I have come to understand(being a non pilot) air to air refueling takes a lot of practice to get right.I realise that his argument about fuel usage/weight is a valid point.But from a safety aspect would you like to try to find a tanker and hook up in turbulence?
Thought Air force one was crewed by military guys anyway.
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Old 23rd Jul 2005, 15:28
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I'll have a pint of whatever the author was drinking please.

Not the safest manoeuvre. I had one trip on a tanker years ago (ANG KC97 -the one in the Dayton museum btw) everyone wearing a 'chute and considerable briefing beforehand.
One point not mentioned; aircraft departs with minimum fuel load, second aircraft, carrying loads of fuel departs. Highest fuel burn is during take-off so it's just been doubled.

Aircraft could refuel over the North Sea. Yeah, right. OK if there's just one, maybe. But get ten or so trying to do it at the same time in a very busy bit of airspace and ....

Bet the same guy will shortly prove bumble bees can't fly.
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Old 23rd Jul 2005, 15:32
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I wonder if they also have though of air-to-air toilet waste removal? And the booze

But seriously, from my understanding of AAR is the optimum altitudes are around FL250ish. That would mean a great deal of climbing and descending around these "air gas stations" from optimum cruise levels, which could get very busy indeed. Throw weather/turbulence and FLEX tracks into the equation......what a mess.
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Old 23rd Jul 2005, 15:45
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The planning of AAR, rendezvous between tanker and receiver, achievement of contact and transfer of fuel requires considerable training and practise. Military aircraft refuel in designated AARAs or ALTREVs and at heights which are not particularly suitable for optimum cruise for civil airliners. Whilst refuelling the aircraft do not comply with MNPS requirements; the modification of aircraft to receive fuel adds structural weight and the process of AAR is not conducive to passenger comfort.

Routine AAR cannot be carried out unless both aircraft are visual with eachother prior to contact; this may also require FLIR or similar systems at night.

The paper is UTTER nonsense; whilst it may be convenient for Air Force One not to have to land (due to security issues) for extended periods, AAR for modern, fuel efficient civil aircraft is simply not needed.

The argument concerning fuel usage is a total fallacy - don't forget about the fuel which the tanker would have to burn!
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Old 23rd Jul 2005, 16:01
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I must say, I've often wondered if the idea of ATA fueling was abandoned to early in civil aviation. If the initiatives of the 1930s' had been continued, we might now be in a situation where the infrastructure/saftey/training issues had long been resolved.

I've also wondered how much more viable Concorde may have been had it had the unlimited range ATA provides.

I agree that, as it is such a fundimental change in the way civil aviation operates, it is unlikely to ever be implemented, but iti is never the less an interesting concept.

As to the extensive training required, during the Falklands conflict the Vulcan pilots who staged the quite incredible missions from UK bases had never ATA refueled until two days before the mission!

Amasing whet can be achieved with sufficient will.
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Old 23rd Jul 2005, 16:09
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Thumbs down

This has to be the most ridiculous suggestion I’ve heard in years.

- Military pilots train long and hard to achieve a qualification with regular practice.
- The thought of airliners bumping along over the GNAFA in pitch black, round CBs, and in moderate chop would fill me with horror.
- What happens if the probe breaks?
- What happens if it’s too turbulent to hook up?
- How will we cope when Big hog the tanker at Lambourne because there’s 10 minutes holding?

Time to check the medication methinks doctor.
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Old 23rd Jul 2005, 16:28
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Wizofoz, As one of the Victor Air to Air Refueling instructors who taught the Vulcan crews prior to their Falkland sorties I'm not quite sure where your two day story came from. The facts were that the Vulcan crews had four receiver sorties and, with one notable exception who ended up in Rio with a broken probe, carried their Victor pilots on their operational trips. It is also worth pointing out that the Vulcan was the most pleasant of all RAF multis in the receiver role. I certainly do not wish to minimise the Vulcan crews achievements, merely to observe that, even with such a benign aircraft, skill and confidence (a vital element when you are hitting something attached to another aircraft very close to you) does not come easily with just two sorties.

Last edited by Art Field; 23rd Jul 2005 at 16:49.
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Old 23rd Jul 2005, 16:38
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Even when completed by two well trained crews, the risks associated with AAR exceed those we would want of air carrier aircraft. Every now and then grief happens to trained aviators during the process. There the risk analysis falls in favor of continued AAR for mission accomplishment. In the civilian world I simply don't see the trade off. The risk is not worth the gain.
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Old 23rd Jul 2005, 17:02
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And........

Will you be paying by cash or charge? Would you like to buy a plane wash as well?


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Old 23rd Jul 2005, 20:21
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From my experience (several atlantic crossings as AAR-receiver, instructorpilot) I do not see the civil aviation with the need for AAR. The training needed is based upon a military pilot carreer i.e. formation flying.
- So just from the basic training - not recommended.
- operational wise (airspace restriction etc) - not recommended
- economicaly from my point of view - not recommended.

Allover: what a strange idea!!
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Old 23rd Jul 2005, 20:49
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Would you like to buy a plane wash as well
of course if you ham it up you get a plane wash for free................ methinks Mr Green needs a holiday.
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Old 23rd Jul 2005, 20:55
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My background is as a large aircraft receiver and whilst I broadly agree with most of the foregoing comments I believe that "if",and it's a very big "if", there was a sound financial/environmental case for civil AAR then it would be made to happen. It would require new technology and systems (I really can't start to think what these might be) but if the business case was there, then it could/would become possible. However, having read the article in today's Times I can't really see that the case was made. Civil AAR is most unlikely to occur.

BTW Wizofoz


the Vulcan pilots who staged the quite incredible missions from UK bases
Not from the UK but Ascension Island. Although it is worth recalling that 101 Sqn flew UK-Australia non-stop with AAR in the '60s

YS
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Old 23rd Jul 2005, 21:22
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A 101 Sqn VC10K also flew non-stop UK-Australia with AAR in Apr 1987. I believe the 15hr 53 min record still stands....
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Old 24th Jul 2005, 00:32
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Art Field and Yellow sun,

Thanks for the clarifications, was writting from pure memory (and I was 17 at the time!!)

All the points made have been valid and, as I said, the huge, fundemental change in civil operations would probabley make this a non starter BUT, if there were an overwhelming economic advantage, no doubt the problems would be overcome.
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Old 24th Jul 2005, 09:04
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Even though the only thing I ever had trouble keeping plugged in was a heavy two seat Harrier that did not really have enough push to deal with a Victor centre hose at high altitude I offer some comments.

Some people seem to be assuming that lots of civil flights could finish up doing AAR but that was not how I read the thrust of the article.

Some people are worried about not getting fuel. Why? Just another case for a diversion.

I think all of the present military need for skill, currency requirements and associated issues would never apply because a civil system would only be certificated if it was easy and safe – namely automatic. If I was a boffin I would sooner have to develop such a system than one that actually lands the aircraft when the crew can not see the runway because of fog. A FBW drogue that homed on a probe would not stretch modern robotics at all.

As a passenger I would be pleased not to have 20 hours fuel on board when any abnormality transpired during take-off.

I see modern airliner and cargo operations as a pure market driven commodity and so would not rule out any development (not just AAR) that might become possible in the future if it opened a new market or gave a competitive advantage in an existing one.

Pilots in general have been too quick to shout NO regarding many things in the past which have nevertheless happened very nicely thank you. In my view by doing this they weaken their case to be treated as thinking professionals. A more reasonable response that results in them being asked to the meetings is “Sounds a good idea but we will need to resolve a few issues first”

Finally, think about how any exhaust gases that we dump in the atmosphere below the tropopause get mixed and washed out by weather. The same stuff dumped in the stratosphere stays there. The pressure to cruise lower is going to come. That will change designs and operational procedures to put it mildly.
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Old 24th Jul 2005, 09:12
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With the A345 and 777ER being able to link almost every major city pair in the globe, who needs it?
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Old 24th Jul 2005, 09:41
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SR71

I exect our posts crossed. In which case I'm sorry.

If they didn't I rest my case.

JF
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Old 24th Jul 2005, 12:45
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But surely if you cruise lower than your optimum FL, you burn more fuel hence more pollution! Surely the answer must be to ban all cars & air travel & bring back the sail boat. That would keep the raving greenies happy. Personally I would rather cruise at a lower level, not because of fuel burn, but due to the fact that I value my tessies.
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Old 24th Jul 2005, 15:07
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John Farley, your point re a FBW system is, as always, well made. The interesting fact is that AAR using the probe and drogue system as invented by Sir Alan Cobham has really not changed at all from its origin just after the second war. I wonder if a FBW system could cope with a bouncing drogue or come to that whether the passengers could cope with a FBW system chasing a bouncing drogue.

You may be able to dampen the receiver responses but damping the drogue ?. Nonetheless one would not wish to stand in the way of progress and I know there are many service pilots around the world who would welcome such an advance.

Last edited by Art Field; 24th Jul 2005 at 18:56.
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Old 24th Jul 2005, 15:18
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A reasonable amount of progress has been made towards drogue stabilisation and autonomous AAR, particularly for UAV refuelling.

But for any airline application, the boom method would probably be simpler and would provide higher transfer rates.

A commercial airliner would need to take-off to make good a RV time (try telling that to ATC flow control!), climb to cruise level, descend to AAR level, find the tanker, achieve contact, take-on the required fuel load, then depart, climb back to cruise level and continue... If the transfer failed, the airliner would still need to make a safe landing somewhere; if the reason for requiring AAR is to increase ZFW and reduce fuel load, that'd mean arriving somewhere with several hundred pretty annoyed passengers.

And who would sell a ticket for a flight which was intending to depart with insufficient fuel to make its scheduled destination!
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