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KC-777. What Would It Take For Wing Tip Booms?

Sun Jul 16, 2006 5:28 am

This got me thinking because out of curiousity, I measured out the distance between the number 1 and number 4 engines on the A340, which of course shares the same wing as the A330. (KC-30) Such an aircraft could boom refuel two F-22's simultaneously with more distance between the boom and the engine than is seen on the KC-10.

Obviously, some redesigning would have to be done to the 777's wing, but would this make the KC-777 more atractive to the USAF to have two outer wing booms?

Just thinking out loud here.
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ptrjong
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RE: KC-777. What Would It Take For Wing Tip Booms?

Sun Jul 16, 2006 7:41 am

You'd need two boom operators. Better bolt a probe on the F-22 like the rest of the world is using biggrin 

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10boomer
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RE: KC-777. What Would It Take For Wing Tip Booms?

Sun Jul 16, 2006 12:42 pm

There would be a lot of stress put on the wing from the loads generated by a receiver in contact, not to mention if there was a brute force disconnect or some other incident. Another issue is the aerodynamic effects caused by the bow waves of large receivers (C-5, E-4 etc.) seems like it would take a lot of aileron trim with a C-5 on the boom. It just doesn't seem like a feasible concept
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RE: KC-777. What Would It Take For Wing Tip Booms?

Sun Jul 16, 2006 11:02 pm

Again, I was just thinking out loud guys.

Quoting Ptrjong (Reply 1):

True, but from what I understand, the next generation boom operators will be using a type of 3-D camera system while sitting at a computer station.

Quoting 10boomer (Reply 2):

I agree. I guess I should have stated that I was curious about wing mounted booms to compliment the main "body boom". The application in my thinking was for simultaneous refueling of smaller aircraft via wing boom, and larger aircraft with the standard body boom. This would fit in the Pentagons desires to provide rapid refuelings.

Another non topic related question though. Are there and booms out there with probe servicing capability? Or is it just the drag chute? (not sure of the technical term, sorry)

Thanks again guys.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 12:20 am

the wing would have to become far thicker and stronger than it is now.
That's the reason why the KC-10 doesn't have it (but has optional underwing hose/drogue pods).

Quoting Boeing Nut (Reply 3):
Are there and booms out there with probe servicing capability?

Yes, the boom on the KC-10 can be fitted with a drogue and hose, but if fitted it can't use the boom directly (it has to land and the hose removed).
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 2:15 am

Quoting Jwenting (Reply 4):
Yes, the boom on the KC-10 can be fitted with a drogue and hose, but if fitted it can't use the boom directly (it has to land and the hose removed).

You're probably thinking of the KC-135. The KC-10 has dual capability at all times since it is equipped with both the boom and a hose/drogue (and can be additionally fitted with the wing hose/drogue pods). The 135 can have the hose/drogue fitted to the boom on the ground, and there are a limited number of wing pods available to the fleet. I've heard that US Navy pilots (sorry...aviators) much prefer the hose/drogue of the KC-10 due to it being more flexible than the short, fairly inflexible rig provided by the 135's boom which has been known to be less forgiving and more prone to slapping around and breaking parts off receiving aircraft ,like probes and pitot tubes, etc. which can be ingested by the engines and make for a bad day when you're a long way from land or a friendly base...
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 4:38 am

Quoting Boeing Nut (Reply 3):
from what I understand, the next generation boom operators will be using a type of 3-D camera system while sitting at a computer station.

Probably, as the Dutch 'KDC-10s' have such a remote control system already. I was thinking that even so, it would be difficult for one person to operate two booms, but maybe not.

Quoting Ptrjong (Reply 1):
the rest of the world

I'm contradicting myself here. Yes, the Dutch and the Israelis and the Turks and the Singaporeans I think do use the boom system.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 7:31 am

Quoting Ptrjong (Reply 6):
it would be difficult for one person to operate two booms, but maybe not.

We're good but not that good, working simultaneous flight control malfunctions, breakaways, etc would be practically impossible

Quoting Ptrjong (Reply 6):
I'm contradicting myself here. Yes, the Dutch and the Israelis and the Turks and the Singaporeans I think do use the boom system.

Don't forget Norway, Denmark, Germany (F-4), UAE , Belgium, Japan, Australia (Wedge Tail), Italy bought the KC-767 with a boom. I'm sure I'm forgetting some others
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 8:11 am

Quoting 10boomer (Reply 7):
Don't forget Norway, Denmark, Germany (F-4), UAE , Belgium, Japan, Australia (Wedge Tail)

Yeah but most of these countries don't have their own tankers.

[Edited 2006-07-17 01:11:47]
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 1:49 pm

Really if you want to fit wing-tip booms, I think the Lockheed box-wing concept is the only feasible option: http://www.lockheedmartin.com/wms/fi...5161&rsbci=13145&fti=0&ti=0&sc=400

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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 17, 2006 9:58 pm

^^That's quite an interesting design.

I'd like to see innovative concepts like that, and like the blended-wing design, take to the air one day, provided that they are economically feasible.

Another interesting wing design that occurs to me, and, as I recall, one that actually did make it from the drawing board into the skies, is the reverse-wing design that I believe they implemented on an experimental F-16 (not the F-16XL). In any event, the aircraft sported wings that looked like they were put on backward (i.e., the wings swept forward).

[Edited 2006-07-17 14:59:22]
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 18, 2006 1:04 am

Quoting AerospaceFan (Reply 10):
is the reverse-wing design

That was the X-29 and I believe it was from Grumman.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 18, 2006 2:19 am

X-29! Ah, yes. It was based on the F-5 fuselage, then I would imagine. Thanks for the correction.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 18, 2006 3:14 am

Quoting AerospaceFan (Reply 12):
X-29! Ah, yes. It was based on the F-5 fuselage, then I would imagine. Thanks for the correction.

We may be getting way off-topic here but yes, the forward-swept wing had been in and out of the limelight like the oblique wing "flavor of the month".....

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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 18, 2006 7:21 am

Thanks for those great pics!

About the 777 as a tanker -- the idea is intriguing. It's a lot bigger than the 767, let alone the KC-135.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 19, 2006 6:05 am

Quoting AerospaceFan (Reply 14):

Guess thats make KC-30 the perfect choise for the Tanker program, nes pas?

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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 19, 2006 9:35 am

The proposal that is under study has the possibility of a 777 tanker as a part of a mix of aircraft or just it alone. The Air Force has differing opinions on the subject. The 777 was suggested as a possibility as it would offer cargo capability in addition to refueling. The 767 won't do that as it will be a dedicated fueling aircraft that won't carry cargo at the same time. But the Air Force is saying thats not a bad thing as they aren't particularly interested in a mixed mission capability. Instead a dedicated mission aircraft like the 767 is what they prefer in some circles.
The traditional tradeoff between the 767 tanker and the KC-30 is the footprint. The larger footprint of the KC-30 works against it as it can't be staged at some forward bases and when you can, you can't stage as many as you can the 767. The 777 tanker would have the same problem, hence a mix might be proposed. So its not just a pure problem of carrying capacity. Its more what the Air Force is going to have money for and what the final mission statement will be. Have cargo in there and the KC-30 and 777 are true contenders. Have just refueling and the 767 might just be the right choice.
Just a word on the 767 tanker, its not a commercial 767, its a Air Force spec model. Lots of new stuff like integrated modular systems, wing and controls enhancements, etc make it different. So like the KC-30 having the A340 wing, these birds are not just a "take one off the line and put a boom on it" airplanes. They are military spec airplanes in the truest sense of the word.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 19, 2006 12:39 pm

Quoting Texfly101 (Reply 16):
But the Air Force is saying thats not a bad thing as they aren't particularly interested in a mixed mission capability.

Really? That's news to me. I'm a KC-10 boom and judging by the number of dual-role (mixed missions) we do every year and have been doing, the Air Force seems to be very interested. How do you think all the fighter units (AF & Navy/Marine) get to and from all the exercises and deployments. If you don't have tankers that can handle the dual-role mission you're going to have to task air-lifters to carry the pax and cargo and potentially more tankers to refuel the air-lifters. Unless the Air Force plans on fundamentally restructuring how it does business, it will be a giant step backwards and a waste of money to have to task two or more airframes to do a job that could be (and currently is) done by one.
Being dual-role capable needs to be a pre-requisite for any new tanker.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 19, 2006 12:51 pm

If the USAF went for a mixed fleet of tankers, they should have the KC-10A and KC-777-200LR as multi-mission airplanes and a KC-737-700ER as the dedicated tanker.

Then you don't have the ramp space problems the KC-767 vs. the KC-30 bring to the table.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 19, 2006 12:56 pm

I heard on some of the old tanker threads that they were studying doing a folding wing option. While it would add weight, it would reduce the wing size to that of a KC767. The KC767 is dead in my book after the scandel about them forcing it onto the USAF, and that it is not that much better than the KC135.

Quoting 10boomer (Reply 17):
If you don't have tankers that can handle the dual-role mission you're going to have to task air-lifters to carry the pax and cargo and potentially more tankers to refuel the air-lifters. Unless the Air Force plans on fundamentally restructuring how it does business, it will be a giant step backwards and a waste of money to have to task two or more airframes to do a job that could be (and currently is) done by one.
Being dual-role capable needs to be a pre-requisite for any new tanker.

Isn't it nice not needing 2 planes when one can do the job.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 19, 2006 9:38 pm

Quoting Texfly101 (Reply 16):
Just a word on the 767 tanker, its not a commercial 767, its a Air Force spec model.

Partially correct. It rolls off the line as a commercial model, then gets highly modified in Wichita, I think.

Quoting Texfly101 (Reply 16):
But the Air Force is saying that's not a bad thing as they aren't particularly interested in a mixed mission capability.

10boomer is correct. The USAF wants a multi role tanker that will even include surveillance capability.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Thu Jul 20, 2006 5:12 am

Quoting Boeing Nut (Reply 20):
Partially correct. It rolls off the line as a commercial model, then gets highly modified in Wichita, I think.

No, actually the Air Force tanker has a lot of modifications built into it from the start. Modular control systems are not standard commercial 767 systems. Remember this aircraft is not for export, its a US military plane that is designed to meet their specific needs. And they made some specific needs that are not in the commercial bird. But it is proposed to go thru the commercial line and then get mods at Wichita. Its a very interesting aircraft and sitting on the field in its current livery, a very striking looking warplane.

Quoting Boeing Nut (Reply 20):
10boomer is correct. The USAF wants a multi role tanker that will even include surveillance capability.



Quoting 10boomer (Reply 17):
Being dual-role capable needs to be a pre-requisite for any new tanker.

Well, its been a very hotly discussed topic in the Air Force systems and proposals teams. Looking at the reports and official discussion pages has been a very interesting read. I can see both sides opinions and reasons. But I do agree that a multi-mission aircraft makes sense. But the WarOps guys just don't want anything getting in their way of their mission planning, both in asset management or availibility. A totally dedicated mission asset answers their needs...and those are powerful reasons. They don't want their assets running around on cargo missions. So we'll see what's proposed and what's chosen.
As far as my personal preference, I agree with you. Actually, I think that a total mix of C-17/767/777/A330 makes lots of sense to me. with a 150+ buy, there's lot of room for everyone. The KC-10 has turned out to be a wonderful aircraft. So the mix of KC-135/KC-10 has turned out great. Interservice and international capabilities are also a prime need IMO. Spreading the load around makes for flexibilities that aren't currently available and one of the reason why the KC-135's are staggering under the mission load. Give me a 767 tanker only for the dedicated mission. Add in a 777/A330 tanker/cargo to the mix to do the long hauls. Use a C-17 tanker for the forward base missions that need cargo or fuel into a small strip...but those are just my opinions. I don't buy and pay for them, I only make them.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Thu Jul 20, 2006 5:37 am

Quoting Texfly101 (Reply 21):
Quoting Boeing Nut (Reply 20):
Partially correct. It rolls off the line as a commercial model, then gets highly modified in Wichita, I think.

No, actually the Air Force tanker has a lot of modifications built into it from the start. Modular control systems are not standard commercial 767 systems. Remember this aircraft is not for export, its a US military plane that is designed to meet their specific needs. And they made some specific needs that are not in the commercial bird. But it is proposed to go thru the commercial line and then get mods at Wichita. Its a very interesting aircraft and sitting on the field in its current livery, a very striking looking warplane.

Duly noted.

The flexibility of the multi role aircraft I believe is simplyfied by palletizing other components for other roles. Outside of the tanker role of course.

Regards.
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texfly101
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RE: KC-777. What Would It Take For Wing Tip Booms?

Thu Jul 20, 2006 8:50 am

Quoting Boeing Nut (Reply 22):
The flexibility of the multi role aircraft I believe is simplyfied by palletizing other components for other roles. Outside of the tanker role of course.

Yep, that's true as both the 777 and A330 have very efficient palletized freighter versions. And thats what the Ops planners are concerned with. Using these assets as cargo planes eats into maintenance budgets, allows them to be assigned to non tanker duties, puts them out of use more often due to maintenance overhauls etc. All of which produces conflict inside the operational organizations, particularly if its a shared asset. So there is a group in the Air Force that says, don't give it cargo capability and it won't be a problem. And they have a point. Whether the Secretary agrees with them is still to be seen. I have a very strong feeling that it will be a dual buy if for nothing else than to build a stronger international alliance. I don't think that NG and AB would go to the trouble to put together the consortium if they hadn't gotten a strong signal that a dual buy is possible. A single source buy to Airbus is not even possible. The uproar over that would make McCains witchhunt look like a minor issue.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Sun Jul 23, 2006 3:30 am

Quoting AislepathLight (Reply 19):
I heard on some of the old tanker threads that they were studying doing a folding wing option. While it would add weight, it would reduce the wing size to that of a KC767. The KC767 is dead in my book after the scandel about them forcing it onto the USAF, and that it is not that much better than the KC135.

No, the USAF will never consider the folding wing option on any KC-777 order. That option adds a lot of weight, which translates into reduced offload and other mission capabilities. Also, the KC-767 will still take up a lot less ramp space than a KC-777, even with the wings folded. Remember a B-777-200 is almost twice as long as a B-767-200.

Don't write off the KC-767. The scandel had nothing to do with the airplanes capabilities, just it's lease/procurment.

If you think the KC-767 is not much better than a KC-135, that puts it in pretty good company, in my book. There has never been an airplane designed as well as the KC-135, it has been flying for 50 years. Yes, you can say the C-130 and B-52 have flown longer, but that is not quite true. Those designs have flown a few years longer. But the production #1 KC-135A, tail number 55-3118, is still flying as a KC-135R with the KSANG.

A KC-767 carries the same fuel load as a KC-135, up to 202,000lbs. But, the KC-767 has a slightly better offload capability (on missions under 4,000nm), the same ferry and mission range, and can carry more cargo and troops. On mission ranges longer than 4,000nms, the KC-135R still has the heaviest offload capability of any current or proposed tanker, except for the IIAF KC-747-100 and a possible Boeing proposal KC-747-800, or possible Airbus proposed KC-380-800.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Sun Jul 23, 2006 6:51 am

Quoting KC135TopBoom (Reply 24):
Don't write off the KC-767. The scandel had nothing to do with the airplanes capabilities, just it's lease/procurment.

KC135: I am a Boeing lover... there is not much that I would rather see than our crazy government  Yeah sure deciding on a Boeing product for the new tanker. The fuck up with the Boeing, congress, and the USAF has had messed up its chances. Had that not occurred, I think that they would have already decided on taking the KC767s. But now, we have to discuss this, and even bring Airbus into the discussion. If you are going for big airframes, forget the KC30, and go with the KC777. For everything Airbus brings to the table, Boeing one-ups them.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Jul 24, 2006 8:37 pm

Quoting AislepathLight (Reply 25):
If you are going for big airframes, forget the KC30, and go with the KC777. For everything Airbus brings to the table, Boeing one-ups them.

I agree.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 25, 2006 7:04 am

Quoting Boeing Nut (Thread starter):
Such an aircraft could boom refuel two F-22's simultaneously with more distance between the boom and the engine than is seen on the KC-10.

Why do Tanker threads always get off topic? To get back on topic, I do not believe we will see wing mounted air refueling booms anytime soon.

From a heavy pilots receiver viewpoint, we use the tanker's fuselage to fly visual formation. Yes, the tanker has position lights, but we use the fuselage, backed up by the lights, to keep our position. While in contact, we can't see where the boom connects to the aircraft. Unless the boom is mounted well aft of the trailing edge of the wing, I don't think a heavy receiver pilot will see anything but sky. But then again, you wouldn't be refueling from the wing as a heavy?

But what about fighters (F-22s)? Again I think you run into the same problem. Most fighters have the boom receptacle mounted behind the cockpit. Even though fighter pilots have a great field of view thanks to a canopy, I still think they will be too far forward to have any good visual references ... that or they will be looking straight up!

But even if that was solved, what happens when the tanker enters a turn? (tankers must turn) One receiver will suddenly get low as the wing and boom above him goes up, while the other receiver suddenly becomes high in the envelope as the wing and attached boom comes down ... with the latter situation being extremely dangerous.

Wing mounted air refueling pods (drogues) get around these problems because the hoses are flexible and the receivers are well aft of any wings and/or associated downwashes or jet engine blasts.


Quoting Ptrjong (Reply 1):
Better bolt a probe on the F-22 like the rest of the world is using

Even with WARPs (assuming they are working), we can refuel four boom equipped receivers in less time than four drogue receivers. The transfer rates from the boom are far more superior than that of the drogues.

With these problems yet to be dealt with, I doubt we will see any wing mounted booms in the near future.

Just my two cents ...

-Pat
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 25, 2006 6:06 pm

Quoting Dc1030guy (Reply 27):
From a heavy pilots receiver viewpoint, we use the tanker's fuselage to fly visual formation. Yes, the tanker has position lights, but we use the fuselage, backed up by the lights, to keep our position.

That is correct, that is why heavies will only refuel from the tail mounted boom.

Quoting Dc1030guy (Reply 27):
Wing mounted air refueling pods (drogues) get around these problems because the hoses are flexible and the receivers are well aft of any wings and/or associated downwashes or jet engine blasts.


Quoting Ptrjong (Reply 1):
Better bolt a probe on the F-22 like the rest of the world is using

Even with WARPs (assuming they are working), we can refuel four boom equipped receivers in less time than four drogue receivers. The transfer rates from the boom are far more superior than that of the drogues.

With these problems yet to be dealt with, I doubt we will see any wing mounted booms in the near future.

That is also correct. The wing tip refueling pods trail the drogues far enough aft to get the receiver out of most turbalance and still give him a good position holding picture. Additionally, the pods are also equipped with lights (but not a full set of pilot director lights) to give him additional information. Drogue refueling is very slow, compared to boom refueling. When I flew the KC-135A, I could refuel 3-4 USAF F-4s to full tanks in the same amount of time I could refuel 1 USN F-4 to full tanks.

But back to the topic. I would guess there will be a significant engineering cost needed to strenghten the outboard wings of a KC-777 (B-777-200LRF) to carry the WARPs. Yes, this can be done, as it was done to the Italian and Japanese KC-767s as well as the RAF A-330TT. The RAAF A-330MRTT (much closer to a KC-30 configueration) is using the A-340 wing with the additional spar (intended to support the A-340s outboard engines) that most A-330s and the A-330TT don't have.

The outboard wing strenghtening was also completed on both the KC-135R and KC-10A when WARP was added to those airplanes, as they (too) were not originally designed to carry wingtip air refueling pods.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 25, 2006 11:41 pm

Quoting Dc1030guy (Reply 27):
Why do Tanker threads always get off topic?

I don't understand why that was off topic. It was a relevence comparing the distance between a fuselage mount boom on the KC-10 to the "wing boom" on the KC-30(X). I made the reference to show there was actually a greater distance between the "wing boom" and the tankers engine than there is between the KC-10's boom and the centerline engine. Not taking into consideration the higher tail mount of course.

Quoting Dc1030guy (Reply 27):
But what about fighters (F-22s)? Again I think you run into the same problem. Most fighters have the boom receptacle mounted behind the cockpit. Even though fighter pilots have a great field of view thanks to a canopy, I still think they will be too far forward to have any good visual references ... that or they will be looking straight up!

But even if that was solved, what happens when the tanker enters a turn? (tankers must turn) One receiver will suddenly get low as the wing and boom above him goes up, while the other receiver suddenly becomes high in the envelope as the wing and attached boom comes down ... with the latter situation being extremely dangerous.

Wing mounted air refueling pods (drogues) get around these problems because the hoses are flexible and the receivers are well aft of any wings and/or associated downwashes or jet engine blasts.

Excellent points. Ones that hadn't occured to me before.
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RE: KC-777. What Would It Take For Wing Tip Booms?

Tue Jul 25, 2006 11:44 pm

Quoting KC135TopBoom (Reply 28):
Drogue refueling is very slow, compared to boom refueling. When I flew the KC-135A, I could refuel 3-4 USAF F-4s to full tanks in the same amount of time I could refuel 1 USN F-4 to full tanks.

TopBoom,

I forgot to ask this before. Have bigger diameter drogues been considered to eleviate this problem?
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 1:18 am

Quoting Boeing Nut (Reply 30):
TopBoom,

I forgot to ask this before. Have bigger diameter drogues been considered to eleviate this problem?

The drogue is actually the aerodynamic basket. The basket is designed to put maximum drag on the hose to help stabilze it and reduce "hose whip". Inside the basket is the probe's receptical where the fuel comes down the hose. This hose is limited in size to about 4" (112mm), IIRC. The receptical, in the drogue has a spring loaded valve the probe opens when the receiver probe seats in the receptical, called a poppet valve. This valve creates a venturi effect when fuel is transfered, thus limited the amount of fuel that can get through. This is one reason why fuel transfer is so slow with probe and drogue refueling. The other main reason is the hose itself. Tankers, and most other airplane fuel systems pressurize their fuel manifolds to about 45psi of pressure. The hose for the drogue can easily handle this much pressure. But, as we all know, the longer the hose must get, the lower the pressure will get.

Additionally, most probe and drogue (except some heavy RAF and French AF airplanes) are smaller airplanes, light fighters (when the size is compared to the tanker or other heavies), and have fewer fuel tanks that receive the fuel. So, in the KC-135 or KC-10 for example, not all of the air refueling pumps are used. IIRC, in the KC-135, we only used one or two pumps out of four.

So, to answer your question, no, increasing the size of the drogue will not increase the rate of fuel transfer.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 2:37 am

Top Boom,

If it wasn't for you on this forum, a bunch of crazies would be running around with all sorts of wild immaginary ideas as to how to AAR, and what is the best AAR plataform.

All without the benefit of even a single observation flight on a KC, or its lesser foreign equivalent.

p.s. You ever fly in the old KC with the J57's with water injection??
MODS CAN'T STOP ME....THEY CAN ONLY HOPE TO CONTAIN ME!!!
 
Boeing Nut
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 2:38 am

Quoting KC135TopBoom (Reply 31):

I understand, thanks!
I'm not a real aeronautical engineer, I just play one on Airliners.net.
 
aislepathlight
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 4:09 am

Quoting RAPCON (Reply 32):

If it wasn't for you on this forum, a bunch of crazies would be running around with all sorts of wild immaginary ideas as to how to AAR, and what is the best AAR plataform.

All without the benefit of even a single observation flight on a KC, or its lesser foreign equivalent.

p.s. You ever fly in the old KC with the J57's with water injection??

I think that the Mil-av forum has a good group of posters now. We seem to all have figured out that if you have any questions about tankers, TopBoom is the man to ask, and you should never challenge him. We have had way too many tanker threads, but they are always fun.

Back to the topic. So is a small diameter, high pressure hose better than a wider, lower preasure hose?
bleepbloop
 
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kc135topboom
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 4:48 am

Quoting RAPCON (Reply 32):
Top Boom,

If it wasn't for you on this forum, a bunch of crazies would be running around with all sorts of wild immaginary ideas as to how to AAR, and what is the best AAR plataform.

All without the benefit of even a single observation flight on a KC, or its lesser foreign equivalent.

p.s. You ever fly in the old KC with the J57's with water injection??



Quoting Boeing Nut (Reply 33):
I understand, thanks!

Thanks guys. But, I am not the only one here. We also have a KC-10 Boomer who drops in from time to time, as does AWACS Lt. Both of them also know a lot about AAR. Yes, I have most of my time in the KC-135 flying the "steam jets". I flew both the KC-135A and the KC-135Q, both had J-57s (military designation of the P&W JT3C) that converted JP-4 and water to smoke and noise. BTW, since these are the same airplanes that are still flying today as KC-135Rs, they are all "old", LOL.

Quoting AislepathLight (Reply 34):
So is a small diameter, high pressure hose better than a wider, lower preasure hose?

Not really. The size of the hose must match the standard size of the tanker and receiver fuel system plumbing, which is 4" or 112mm. A smaller diameter hose will increase the fuel pressure. With the hose lenghting and shortening during refueling, it will be very difficult for the tanker crew to assure the pressure dies not exceed 45 psi, that could damage either the tanker's or receiver's fuel system. Additionally, a smaller hose operationg at a higher pressure does not really translate into more fuel transfered in the same amount of time.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 6:50 am

Quoting KC135TopBoom (Reply 35):
I flew both the KC-135A and the KC-135Q, both had J-57s (military designation of the P&W JT3C) that converted JP-4 and water to smoke and noise. BTW, since these are the same airplanes that are still flying today as KC-135Rs, they are all "old", LOL.

Dude, I was a controller at Torrejon AB, and during those nice hot/high summer days of central Spain (TJ's elevation is 1994ft), the J57 powered KC's had to back-taxi all the way to the end of the approach threshold. We had to hold all traffic while watching the smoke build up as the water dropped all over the f***ing place!! Those KC's were sooo loaded that sometimes it would take almost 10,000 ft to get airborne (TJ'r rwy is 13,400ft with 1000ft overruns at both ends)!

Nobody ever crashed!!

p.s. Don't feel to bad, the Spanish AF's MirageIII also took a long time to get going during the summers!
MODS CAN'T STOP ME....THEY CAN ONLY HOPE TO CONTAIN ME!!!
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 7:32 pm

Quoting RAPCON (Reply 36):
Dude, I was a controller at Torrejon AB, and during those nice hot/high summer days of central Spain (TJ's elevation is 1994ft), the J57 powered KC's had to back-taxi all the way to the end of the approach threshold. We had to hold all traffic while watching the smoke build up as the water dropped all over the f***ing place!! Those KC's were sooo loaded that sometimes it would take almost 10,000 ft to get airborne (TJ'r rwy is 13,400ft with 1000ft overruns at both ends)!

Nobody ever crashed!!

Yeah, I saw both ends of a lot of runways, while still in a 3 point attitude (wheels still on the ground), LOL. I remember we were dragging F-106s (they launched from Griffiss, we launched from Pease) to NAS Kiflavic, Iceland. We had the F-106 Squadron Ops Officer in our jump seat (he was an F-106 IP). As the departure end of the Pease AFB runway (11,450') was rapidly approaching, as we accelerated to about the 165 knot rotation speed (we were very heavy), J-57s just screaming, he began to get very antsy. With about 1,000' to go on the runway, Sid (our pilot), slowly began to rotate the tanker. The F-106 IP was standing in the jump seat, trying to find a way out of the airplane. He just couldn't take any more. I just laughed at him and said "not such a big bad fighter pilot after all"?

BTW, we did lose on KC-135A and crew at TJ. They crashed after losing water to the inboard engines, and hit the hill west(?) of TJ.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Wed Jul 26, 2006 9:41 pm

Quoting KC135TopBoom (Reply 37):
BTW, we did lose on KC-135A and crew at TJ. They crashed after losing water to the inboard engines, and hit the hill west(?) of TJ.

Must've been way before my time (84-87).

No hills west of TJ, only MAD Int'l and Madrid itself. There is a hill S-SE, but only the fighters flying VFR eastbound would fly over it; a loaded KC would've never been allowed to take off S-SE due to the proximity of the town of Torrejon just south off the departure end of RWY 23. You sure it was not Zaragoza AB? (they had hills west)

p.s. I lost an F-16 against that hill S/SE of TJ--pilot got vertigo in a low cloud, went inverted, and SPLAT!!! About 16grams left of him.
MODS CAN'T STOP ME....THEY CAN ONLY HOPE TO CONTAIN ME!!!
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Thu Jul 27, 2006 12:15 am

Quoting RAPCON (Reply 38):
Must've been way before my time (84-87).

No hills west of TJ, only MAD Int'l and Madrid itself. There is a hill S-SE, but only the fighters flying VFR eastbound would fly over it; a loaded KC would've never been allowed to take off S-SE due to the proximity of the town of Torrejon just south off the departure end of RWY 23. You sure it was not Zaragoza AB? (they had hills west)

It could have been Zara, but I thought it was TJ. It happened back in 1976, IIRC, or within a year either way. IIRC, it was a crew out of Grissom AFB, IN.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Thu Jul 27, 2006 2:20 am

Quoting KC135TopBoom (Reply 39):

It could have been Zara, but I thought it was TJ. It happened back in 1976, IIRC, or within a year either way. IIRC, it was a crew out of Grissom AFB, IN.

Found it!!! You were right, it was at TJ.

Serial Numer 58-0001/0039 (KC-135Q) crashed into hill Jun 13, 1971, during approach at Torrejon AB, Spain.

So on an approach to RWY23 (no landings allowed on RWY5) he must have hit the mountains to the E/NE (the closest are about 8-10nm away), which would put the a/c on a base-to-final instrument approach.

1971! No wonder I never heard of it!

p.s. 135Q....one of those "special tankers" eh?
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RE: KC-777. What Would It Take For Wing Tip Booms?

Thu Jul 27, 2006 3:28 am

Quoting RAPCON (Reply 40):
p.s. 135Q....one of those "special tankers" eh?

Yes, it was initially designed to refuel the SR-71.
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Mon Oct 02, 2006 11:33 pm

Hmmm, why do we even need boom operators these days? Not to disparage our boomer comrades, but going forward, why not have automated linkup between tanker and receiver? Obviously the boom would have to be redesigned, and the receiver would have to have some way of indicating the precise location of the intake.
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dc1030guy
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RE: KC-777. What Would It Take For Wing Tip Booms?

Fri Oct 06, 2006 6:32 am

Quoting Boeing Nut (Reply 29):
I don't understand why that was off topic. It was a relevence comparing the distance between a fuselage mount boom on the KC-10 to the "wing boom" on the KC-30(X). I made the reference to show there was actually a greater distance between the "wing boom" and the tankers engine than there is between the KC-10's boom and the centerline engine. Not taking into consideration the higher tail mount of course.

Boeing Nut:

My apologies sir. The comment was NOT directed towards you; it was for others who started to hijack the thread. Quoting you was meant to bring us back on topic. I apologize for not making that clear.

Like I mentioned earlier, unless there is a way to overcome the challenges I presented above, you aren't going to see wing mounted booms anytime soon. Additionally, you would have to significantly modify existing tanker aircraft and you would need two boom operators.

Quoting N328KF (Reply 42):
Hmmm, why do we even need boom operators these days? Not to disparage our boomer comrades, but going forward, why not have automated linkup between tanker and receiver? Obviously the boom would have to be redesigned, and the receiver would have to have some way of indicating the precise location of the intake.

Is this possible? Yes, with a lot of dollars we don't have. But realistically, I think it just isn't practical. If you did, you would regret because I think accidents would siginificantly increase and the probability of having successful contacts would decrease. Why?

Our boom operators provide priceless feedback to the tanker pilot and to the receiver pilot ... not to mention, they coordinate the arrival / departure of fighters flying visual formation with the tanker.

Also, I've been in situations where, had it not been for our experienced boomer, we would have splashed a fighter or two. Boom operators have a knack for making contacts with struggling receivers that simply would not be possible with an automated system. Whether it was coaching the receiver pilot into position, giving him morale support, or taking life by the horns and forcing a contact even though the pilot was out of optimum position, boom operators make air refueling possible.

And lets not forget, boomers are also load masters, flight attendants (even though you'll never get one to admit this), and most importantly, a safety observer in the cockpit for takeoff and landing ... and have prevented many pilots from inadvertently making stupid mistakes.

I could go on for hours why having a boomer is priceless. But until you go and see what they bring to the fight, or have refueled from a tanker, you just aren't going to understand.

Pat
 
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RE: KC-777. What Would It Take For Wing Tip Booms?

Sun Oct 08, 2006 9:12 am

Quoting Dc1030guy (Reply 43):
Quoting N328KF (Reply 42):
Hmmm, why do we even need boom operators these days? Not to disparage our boomer comrades, but going forward, why not have automated linkup between tanker and receiver? Obviously the boom would have to be redesigned, and the receiver would have to have some way of indicating the precise location of the intake.

Is this possible? Yes, with a lot of dollars we don't have. But realistically, I think it just isn't practical. If you did, you would regret because I think accidents would siginificantly increase and the probability of having successful contacts would decrease. Why?

Our boom operators provide priceless feedback to the tanker pilot and to the receiver pilot ... not to mention, they coordinate the arrival / departure of fighters flying visual formation with the tanker.

Also, I've been in situations where, had it not been for our experienced boomer, we would have splashed a fighter or two. Boom operators have a knack for making contacts with struggling receivers that simply would not be possible with an automated system. Whether it was coaching the receiver pilot into position, giving him morale support, or taking life by the horns and forcing a contact even though the pilot was out of optimum position, boom operators make air refueling possible.

And lets not forget, boomers are also load masters, flight attendants (even though you'll never get one to admit this), and most importantly, a safety observer in the cockpit for takeoff and landing ... and have prevented many pilots from inadvertently making stupid mistakes.

I could go on for hours why having a boomer is priceless. But until you go and see what they bring to the fight, or have refueled from a tanker, you just aren't going to understand.

Pat

Thanks Pat. But, I was never, and will never be a flight attendent, I briefed and controlled the pax. I cannot speak for the KC-10 Boom Operators, but in the KC-135A/E/Q, when I flew, the BO also had all the systems knowledge on the airplane, and easily helped the P, CP, or N with what ever systems problems they had. KC-135 BOs also shot the sextant (and us older IBOs did the precomps) for the Ns.

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