AAR Technique Q

[CoffmanStarter]

The Lossie Statish has just tweeted a couple of cracking pics ...

https://pbs.twimg.com/media/BIY0Q9eCQAAlmsO.jpg

https://pbs.twimg.com/media/BIY0zFVCEAAjdAM.jpg

Just wondered if someone could explain a little about the difference in AAR technique from the conventional RAF Trailing Hose Drouge config to that of the Boom Drouge Adaptor arrangement shown here ...

For example is the Boom Drouge Adaptor flown on to the receiver aircraft by a guy in the back of the KC10 ... or does the receiver line up/dock as per Trailing Hose.

Sorry if it's a bit of an anorak question ... but genuinely interested in the techniques and preferences of the user community :ok:

Looks like a very short bit of hose on that boom :eek:

Cheers ...

Coff.

[5 Forward 6 Back]

You treat it like a normal trailing drogue arrangement; the boom's extended to maximum and positioned to the left, and you do the rest.

Because there's no HDU to start the flow, once plugged in, you needed to manoeuvre a certain way to get the flow to start, by putting a bend in the hose and opening a valve or 2.

Much more challenging than regular AR. Plugging in was arguably easier as the bow wave didn't affect the metal basket as much, but you had very little in the way of references and had to fly with the basket lined up on one of the tanker's wings. Very little room to manoeuvre once plugged in, and we've all seen people coming back without probe tips or in extremis, with parts of the basket attached to the jet!

[Courtney Mil]

Anorak, Coff? Heaven forbid!!

The boom stays still and the receiver plugs as usual. You then have to push forward to put the 90 degree bend in the hose coupling to let the fuel flow. It has a few more hazards than a HDU and is nowhere near as straightforward.

I wrote a piece about it some years back:

Tanking from the Boom (http://www.projectoceanvision.com/vox-10.htm#AAR)

[BEagle]

The receiver makes a normal approach to contact when cleared - the boom operator doesn't move the boom...

...until you miss. Then they might - which is a right pain in the ar$e as it destroys your visual references. When in contact, you have very little latitude of movement, but at least the fuel flows very quickly.

The first (and only) time I ever jousted against the wretched BDA was in a Q-fit F-4 with 8 rockets and 3 tanks on a live QRA sortie. I'd never had a dual BDA session, nor even a brief - apart from 'make contact slowly and push it until the valves open' as I was stepping to the jet.....:hmm:

It took quite a few attempts at teach-yourself BDA prodding until I sorted it out - with able encouragement from my navigator who gave some helpful advice. I couldn't understand a word the female boom operator was saying, but eventually 'asked' her to stop moving the damn thing every time I missed. Unfortunately, by the time I'd taught myself BDA prodding, our target Bear had buggered off back to Russia before we could catch it...

I was asked later why it had been 'such a problem'.....:\ "Just another tanker", commented the arrogant Tony-the-P**f :mad:

Funny thing was, when the squadron did some Charlie-fit BDA prodding a year later, they sent a signal thanking the USAF for the valuable training in "Such a different and difficult form of AAR"....:rolleyes: They also lost a couple of probe tips....

I learned about back-stabbing squadron mini-wheels from that!

[CoffmanStarter]

Thanks chaps ... Nice piece Courtney :ok:

Why a metal drogue then ... Did we ever trial the use of the conventional soft Drouge on the BDA ?

5F6B ... Got the use of visual formation cues on the tanker by the receiver ... so for night ops I assume Nav/other lights would provide cues ? Which then begs the question ... can the BDA be used in total blackout ?

Best ...

Coff.

[5 Forward 6 Back]

Coff,

Yes, lining up on a VC10, Tristar, KC-10, KC-135 etc at night was fine with the use of some underbelly lights and a lit HDU for those with wing pods. The KC-10 in particular was quite a relaxing experience as you followed an array of belly lights around the dark sky without much else lit up.

The BDA, thankfully, wasn't cleared for GR4 night AR... used one when there wasn't anything else available at dusk once and I wouldn't have liked to stay any longer...!

[Onceapilot]

Nice pics. Guess the BDA will get more use by the RAF from now on?:)

OAP

[Geehovah]

That was one of my favourite moments in MOD.

One Star: Write me a Service Deviation for the F3 to tank from a KC135 at night

Me: Yes Sir.

Boscombe TP: Its impossible. Shouldn't be allowed while there's a T in Tornado. No lights, shaky basket and very silly couplings.

Mate from front line: It was OK when we did it last week.

Me: Sir we have a problem........................

[vascodegama]

Coff

I doubt it was a KC10 since it doesn't use BDA -only the KC135 (and variants) has that option

[BEagle]

Why a metal drogue then ... Did we ever trial the use of the conventional soft Drouge on the BDA?

I'm not sure that it actually is made of metal?

But because it isn't retractable, it has to cope with the relevant aircraft TAS limits in transit - somewhat higher than those with a normal UK AAR hose extended.

Hopefully the wretched BDA will be $hit-canned soon. It is an appalling system; on 7/18 Jan 1991, 8 Italians Tornados were fragged for a night mission as part of Desert Storm (Op Locusta). 1 went U/S, but the other 7 launched. Due to turbulence and the infernal KC-135 BDA, 6 of the 7 were unable to prod; the other succeeded and pressed on alone. Unfortunately it was shot down, but the crew survived and were captured.

In contrast to the BDA, the KC-10 centreline hose was the easiest thing I ever prodded with the F-4. Victor pods were a pain due to the transfer rate and the centreline was much better; however, the Vulcan centreline was rather easier to prod than the Victor.

[just another jocky]

Guess the BDA will get more use by the RAF from now on?

Been cleared for use for many, many years now so not sure I understand yr question. Not the most fun thing to tank off, especially if short of gas and no other options available.....kinda sorts the men from the boys and all that! :eek:

[5 Forward 6 Back]

It's mostly metal; which I can confirm having watched a sheepish colleague bring one back from the line into ops not so long ago!

[Just This Once...]

I must be one of the boys as the thing is worrying.

First time I saw the BDA we were #2 to a very experienced flt cdr. He went first, in first time, slid left and thereafter remained 'in contact' for unplanned 40 min transit and landing back at Marham.

I presume the engineers sent it back to the USAF once they removed it off the end of the probe.

Couple of weeks later we had a go… the USAF returned the tip of our probe via the post, complete with condoms on it.

It seemed to get easier after that, but not by much.

[Lima Juliet]

Courtney

Talking of...

Anorak

...your cutaway drawing on your Blog (courtesy of Flight International) looks like an F2 to me (or it might be the Boscombe TIARA jet). Two reasons lead me to this conclusion:

1. Forward "course" RHWR antenna.
2. Fillet cut-out at base of fin/rudder by the burner cans.
3. Nav's cockpit is level with intakes.
4. Single Winder LAU on pylons.

Sorry, old boy... :8

LJ

[Courtney Mil]

Hmm. I think I have to agree with all 3 of your 2 reasons there, LJ.

:ok:

Edit: I see your edit and raise you all 4 of your 2 reasons.

[Courtney Mil]

Here's the little bugger. You can see how hard it is compared to a proper basket.

http://upload.wikimedia.org/wikipedia/commons/thumb/4/4a/Boeing_KC-135E_boom_drogue_adapter.JPEG/640px-Boeing_KC-135E_boom_drogue_adapter.JPEG


From ATP 56(B)

AAR Equipment – Boom Drogue Adapter (BDA)

Description
The BDA is 2.74 m (9 ft) of hose attached to the end of the telescoping part of the boom by a swivelling coupling; the hose terminates in a hard, non-collapsible drogue. The telescoping part of the boom is kept fully extended whilst the BDA is in use. The boom will be trailed at the pre-determined boom elevation and azimuth settings for that particular
receiver type.

Basic Operation
The boom operator will hold the boom as motionless as possible, at the proper trail position, from the time the receiver reaches astern until completion of refuelling.
The ideal astern position for the receiver is to be stabilized 1.52 m (5 ft) behind the drogue.


When cleared, the receiver moves forward to make contact; slight scillations of the drogue are normal, and can be expected in even ideal weather conditions. The boom operator will not move the boom except to avoid striking the receiver airplane (the drogue is never “Locked down”).

Simultaneous refuelling from the centreline BDA and wingtip mounted MPRS AAR
pod(s) is prohibited due to inadequate refuelling envelope clearance between receiver aircraft.

Receiver Actions
Extreme caution is required when operating on the BDA because,
unlike hose drum systems, hose slack is not wound in. Contacts made with closure rates greater than about 2 kts will cause the hose to whip, with a consequently high probability of probe damage. Care must be taken to prevent the hose from looping around the probe, or touching the receiver’s fuselage; this can be avoided by the receiver approaching no closer than one half hose length. See Annex ZA, Appendix 2.

Fuel Transfer
When the receiver has made contact, the tanker will transfer a small quantity of fuel to check the integrity of the system; if there are no fuel leaks, normal fuel transfer will continue. If possible, the tanker air refuelling pumps will be switched off 5 seconds before the scheduled disconnect; this is to minimize fuel spray on disconnect.

Fuel Transfer Failure
If fuel does not transfer, the receiver will be instructed to disconnect; the receiver should drop back to the astern position and check that the correct fuel system selections have been made. The boom operator will cycle the boom system by retracting the boom to approximately 6.5 m (15 ft) extension and then fully re-extend it. The receiver will then be re-cleared for a further contact.

Normal Disconnect
When cleared, the receiver should disconnect by backing, remaining aligned with the boom and aim to separate leaving the drogue aligned to its free trail
position. The boom operator does not retract the boom for a normal disconnect. To avoid the drogue striking the aircraft, the receiver pilot must not stray away from the correct lateral alignment.
NOTE
As soon as the receiver is in a safe position, the boom operator will cycle the boom by retracting to approximately 6.5 m (15 ft), then fully extending to signal "Ready for contact". Failure to cycle the boom could prevent subsequent contacts.

Emergency Disconnect
In an emergency the boom operator may retract the boom, in which event the drogue will whip violently as contact is broken.

AAR Equipment Lighting - BDA

Description.
The elevation background lights and letters (PDLs described above in para 3ZA a (7)) will be on during BDA AAR, but will not be used to direct receiver
positioning; the PDLs do not provide correct positioning information during BDA operations. During night AAR, the AAR floodlight, boom nozzle light, and boom marker lights will also be used to illuminate the boom and BDA.

Radio Silent Procedures and Breakaway.
The elevation background lights and letters are used during radio silence to
signal a routine disconnect (lights going out), or command a breakaway (flashing lights and tanker lower strobe light on).

[BOAC]

Further to Courtney's post about 'high closure rates', I tanked a few times in the Lightning from the boom. I think the squadron 'lost' 3 probes in 2 weeks. It was said that if you sent a ripple up the short piece of hose you could not back out quickly enough to avoid circumcision.

[Rhino power]

The KC-10 doesn't use a BDA because it doesn't need one, it already has a hose and drogue... http://www.sov13t.com/jsoh2011/IMG_8705.JPG

-RP

[Rhino power]

apologies for the large image, i think its fixed now... :O

-RP

[Courtney Mil]

RP, if you could make your picture a bit smaller, we could read the rest of the page.

Good picture, though.

[Onceapilot]

JAJ, it was just that we seem a little short of AAR assets. Maybe the BDA will become a regular feature for the RAF? Is that why we see these pics?:)

OAP

[Rocket2]

Sorry for the daft question but when based at Kinloss I tried AAR on the sim & managed about 30 seconds of contact during my 30+ mins in the LH seat. So how did you guys fine tune the approach / cruise speed? Did you just use 1, two or all four throttles? I tried various methods & even allowed for spool up / intertia times but always overshot or fell back. Later tanked direct to ASI & was in the front for both prods (Tristar & VC-10) - the crew made it look so easy, full respect to you guys :ok:

[Courtney Mil]

Part of that may have been a bit of a sim thing - although I'm not faimiliar with the old Kinloss sim. The reason I say that is that after years of flying and tanking, I was given a demo of the excellent GR4 sim at Lossie, which included a bit of AAR. I actually found it quite hard in the sim to start with because of the slight lag in the visual - more difficult than real tanking. I eventually had to resort to shooting down the tanker, a perfectly reasonable thing to do when the prodding isn't going too well.

[27mm]

Ah yes, tanking, also referred to as:

a. A flying f@ck at a rolling doughnut

b. Pushing wet spaghetti up a cat's arse

:\

[A2QFI]

I once tanked in a Jaguar from a USN A4. Very pleasant, a small aircraft flying at good speed and minimal jet wake, Couldn't give that much fuel but a Jaguar couldn't take much!

[Rocket2]

Courtney
Thanks for that - it confirms the comment made by a Nim LH seater when I asked him; I thought he was being polite when he told me that I was doing well to hang on for 30 secs in the sim, especially since the motion was switched off.

[thunderbird7]

Kinloss sim was pretty ropey for AAR, far more sensitive than the real thing.

[Fareastdriver]

Those were the days.
http://i229.photobucket.com/albums/ee224/fareastdriver/ValLight-1.jpg (http://s229.photobucket.com/user/fareastdriver/media/ValLight-1.jpg.html)

[CoffmanStarter]

Thanks again gentlemen ... I Really appreciate all your responses :ok:

I'd have loved to have a go :(

I bet there are a few more interesting tanking stories out there to be told ... so let's be hav'in you :)

I had the very good fortune to meet up with fellow PPruNer Pontifex for a very enjoyable chat over coffee a couple of weeks back ... I'm sure he won't mind me sharing one of his pics that I thought might be of added interest to this topic.

http://i1004.photobucket.com/albums/af162/CoffmanStarter/image_zpsad5dbc0a.jpg

Our man was the Boscombe TP flying the Herc during AAR trials with the Vulcan ... coincidently he was the TP during the Nimrod AEW3 AAR trials. Hopefully if he picks up this thread he will regale us with a few stories !

Courtney ... I think you've tanked off a Herc down in the South Atlantic ... Have you got any pics ?

Best regards ...

Coff.

PS. Leon ... I think it's about time we promoted you to OIC PPRuNe Tech Standards :} clearly you still need a Nav for counting purposes !

[CoffmanStarter]

As an aside ... any recommendations on a good read regarding RAF AAR development and implementation ?

Anyone read this one ? Worthwhile ?

http://www.psbooks.co.uk/image/84475.jpg

Best regards ...

Coff.

[BEagle]

I've just received that* as a gift.

316 pages of pretty detailed information (perhaps too detailed in places - how many people are that interested in Fig. 185. Republic Thunderjet F-84E receiver electrical circuit, for example?) and 348 detailed figures, plus dozens of photos.

Probably the closeset thing to an Encyclopedia of AAR that there is.

*(That Lightning is sitting too low behind that Victor - note the hose angle!)

[CoffmanStarter]

Thanks BEagle ... I'll give it a go :ok:

[iRaven]

Does that book come with a free blanket and pillow? :zzz:

[newt]

Beagle. The hose angle looks fine to me!!

Well I have had a couple so will review in the morning!!!:ok:

[ExRAFRadar]

"Pushing wet spaghetti up a cat's arse"

:D :D

[Courtney Mil]

Beagle. The hose angle looks fine to me!!

It looks low to me too. I know the angle it's taken from doesn't make it easy, but I'd be willing to bet that the hose pinged up a lot on disconnect.

[BOAC]

I'm with you guys. Too low.

[BOAC]

I'm with you guys. Too low. I was told you leave it where you find it.:)

[Courtney Mil]

Agreed. The seat down and the fridge door closed, BOAC. :cool:

[BEagle]

And don't wipe your hands (or anything else) on the curtains or leave bike bits on the kitchen table!

[BOAC]

Agreed. The seat down and the fridge door closed, BOAC. - don't forget - lady's clothes back on:=

How could fighter pilots miss that...........................:confused:

[Fox3WheresMyBanana]

don't forget - lady's clothes back on:=

How could fighter pilots miss that...........................

..because we only wear lady's clothes at Dining In nights

[BOAC]

Damn - me - bit slow there - should have seen that coming as they say.

Can I tentatively add fourth Friday in the month?