Lightning Wing Tanks

Interesting thread. After 13 years working on Lightnings, I never ever saw any tanks, not even as display parts for BoB open days.

Sorry to raise an old thread. But does anybody know what specialist equipment, if any, was required to remove and fit the overwing tanks. Any photos of this operation would be great. Assume there must be a sort of lifting beam ?

XN725

Another shot of XN725 with the trial tanks- shows it was an FMK2 ( with OR946- instruments) and an FMK3 fin.

I do believe that a number of Lightnings were fitted with OWT to simulate the radar signature of the Backfire, also the last flying Lightnings on the Tornado trials were similarly configured.

Thanks John, ICD!

Pagen

XN725 was built as an F.2 and subsequently used as an extensive trials aircraft, sporting several ventral tank arrangements and overwing tank trials, she was also the prototype for the F.3 conversion carrying the square topped fin and straight leading edges.

HTH,

John.

square fin, non cranked wings and small ventral.

Now I’m confused, I thought all of the above is what made an F.3 and F.3, the F.2 having rounded fin, F2A square fin, long tank and cranked wing.
XN725 is pictured in the ’64 Observer book with those tanks (probably same mission) and labelled as an F.3.

Ltg OWT

Here is the 1st Prototype OWT aircraft- an F2 with square fin, non cranked wings and small ventral. White paint to aid jettison trials

surely the main reason the tanks ware fitted over the wings was that the main undercarriage design which occupies most of the wing span precluded their use in the standard under wing position, nothing to do with gravity feed etc. I

Spot on James !…there was simply no where else to put the tanks on the wing !

The Facts

Pagen 01- Your spot on!- The tanks were very rarely used. Early on 11,5 and 74 Squadron used then- 74 Squadron used them to get to Tengah, 11 squadron used them as early users of the FMK6. 23 Squadron took a pair of aircraft to Canada and used them. Then they fell out of popularity in fact from about 1972-1984 they were rarely seen. Then the Falkland Island blew up ( no pun) and a few of the Binbrook wing flew with them on for a while.Pushed back into storage they were next seen in 1987 when OC 5 Squadron took XR770 aloft with the tanks back on. The RAF identified a handful of aircraft for the Tornado ADV trials and these were picked as having lowish fatigue and still having the ability to carry the tanks. aircraft were XR770, XR773,XS904,XS928 and XS923. Last RAF flight with OWTs was june 13th 1988 when Flt Lt Page delivered XS928 to Warton.

Think there are a few larger than life stories developing here!

To right, I haven’t grimaced like this for a long time! Your post makes absolute sense, I was ready to say that the Binbrook QRA aircraft carried the over wing tanks, but taking a quick glance through Ian Black’s book again I’m amazed at how seldom they were actually fitted.
I must stop making Lightning models with the tanks on.

Going back to an earlier point, surely the main reason the tanks ware fitted over the wings was that the main undercarriage design which occupies most of the wing span precluded their use in the standard under wing position, nothing to do with gravity feed etc. I

TonyT the later tanks didn’t have the fins on, it was the earlier tanks, which I thought were trialled on an F.3, but will double check that.

Yup the cartridge units pushed them up into the airflow, If I remember correctly the inital trials when jettissoned and the tanks came off, they rolled inboard to the wing fuselage join and stayed there, he had to pull a few aeros to dispatch them, after that they were fitted with small fins on the rear so when pushed clear by the ERU’s the airflow would flip them off the wing

Think there are a few larger than life stories developing here! Lightnings had over wing fuel tanks- called OWTs they were in fact Ferry tanks that means they were designed to be put on prior to a deployment say the far east. Once the aircraft landed the tanks would be taken off- it was never planned to do combat in them – in fact I think the G limit full was 2.5 empty 4G I can’t recall- also they were subsonic tanks. As to the fuel burn an average sortie with tanks could last 1.30 -1.45 un refueled so it’s not correct that one tank was used before you got airborne hope this helps

This was my recollection too – OWT were for ferry purposes only. Jettison/fitment was achieved by means of a cartridge-operated Ejector Release Unit (ERU) which “pushed” the tank away from the wing. I doubt that the ERU would be capable of raising a full tank to achieve separation. The ERUs were of a similar design to those fitted to Lightning missile packs and Hunter wing pylons.

OWT

To answer your question not all fighters need to jettison tanks in combat- as per my post the lightning tanks were designed as ferry tanks never to be used in combat or supersonic. To jettison fuel two explosive bolts literally opened the back of the tank and fuel poured out the back. English Electric did do some jettison trials with an FMK2 – the early tanks having large fins on the back. As for flying inverted to jettison I think you’d find that would be difficult. As soon as you rolled in vetted the nose would drop meaning you’d be bunting like mad so trying to blow the tanks off would have been a bit fraught. Also the only real emergency in a Lightning was a fire so rolling inverted on fire would also not be a great idea. Once the tanks were empty you really didn’t notice difference in handling – hope that answers you question

Refer back to my earlier post (#15) in this thread with the extract from the pilots notes.

Which refers to jettisoning in “straight & level flight” as part of normal procedures.

It is quite understandable that overwing tanks containing fuel would not separate cleanly in straight & level flight, and thus could seriously damage the aircraft.

My question was if, in an emergency, it was POSSIBLE to jettison overwing tanks containing fuel by inverting the aircraft.

See the difference?

Salad fingers… while I mentioned combat, I was meaning any emergency situation where there was not time to properly dump the fuel from the tanks according to standard procedures.

Lightning Over wing tanks

Think there are a few larger than life stories developing here! Lightnings had over wing fuel tanks- called OWTs they were in fact Ferry tanks that means they were designed to be put on prior to a deployment say the far east. Once the aircraft landed the tanks would be taken off- it was never planned to do combat in them – in fact I think the G limit full was 2.5 empty 4G I can’t recall- also they were subsonic tanks. As to the fuel burn an average sortie with tanks could last 1.30 -1.45 un refueled so it’s not correct that one tank was used before you got airborne hope this helps

Could they be got rid of by hitting the eject switch then rolling inverted (or in the reverse order)?

Refer back to my earlier post (#15) in this thread with the extract from the pilots notes.

Since having drop tanks on when entering combat is a bad idea due to adverse drag etc (see Thomas B. McGuire), even if there is still fuel in them, a Lightning driver might want to be rid of them quickly.

Could they be got rid of by hitting the eject switch then rolling inverted (or in the reverse order)?

Sure I heard from my days at Binbrook, that it took the whole contents from one tank to get them airborne!! So usually took off with them empty then found nearest Shell garage to fill them up . . . maybe a Binbrook myth, but who knows :o)

[Joke ON]

] the tanks were 270 gals each and it required 270 gals to overcome the extra drag.

If a Lightning could carry 540 girls in its overwing tanks, then the RAF should re-deploy some Lightnings to Afghanistan, instead of sub-contracting Vertical-T Mi-26 transport heloes for materiel and personnel transportation…

[Joke OFF]