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stilton
5th Aug 2008, 08:39
Does anyone know how the wing sweep is actuated when in manual on the F1-11, F14, Tornado etc..

My question is not how the actuation takes place but whether the controlling 'lever?' is placed forward or back for sweep / unsweep.

Hope this makes sense..

Morf
5th Aug 2008, 09:22
Tornado:
Lever forward = wings forward.
AWS disabled ..... genius

advocatusDIABOLI
5th Aug 2008, 09:24
Stilton,

In the Tornado (Both F3 and GR4) the wings are moved manually. There was an automatic system fitted to both types, but it was never certified for use and is switched off. The wing sweep lever, is just next to the throttles (left side) and works in the natural sense, ie: forward= wings forward and back= wings back. the wings can be swept to any postion, but normally used in 25(forward) 45 (1/2) or 63/67(back). F14 Tomcat was fully automatic. Don't know about F111. Flogger, is manual, and mostly rubbish! (But can be controlled by 'Mind Control', but only in Russian) :ooh:

Hope this helped.

Advo

stilton
5th Aug 2008, 09:38
Thanks for that, I thought the F 14 had a manual override and wonder if it works in the same manner as the Tornado.

Anyone have the answer to the F111 ?

Olly O'Leg
5th Aug 2008, 09:48
During the design of the MRCA, there was some debate as to whether the wing sweep lever should work in the same sense as the throttles - ie throttles forward to increase speed, wing sweep lever forward to increase speed! :eek: Thankfully the opposite was decided upon in the end.

advocatusDIABOLI
5th Aug 2008, 10:00
Stilton,

Yes it Does. Yes It Does.

Advo

2muchROSO
5th Aug 2008, 10:01
F111 is the same as the GR4, (except it is allowed to fly at any wingsweep setting!)although there was never an automatic option. Always manual, and in the same sense as the GR4/F3.

advocatusDIABOLI
5th Aug 2008, 10:07
My personal favourite was always 35wg, since the fatigue meter didn't read! :ok:

Only Joking.......

Advo

27mm
5th Aug 2008, 12:08
The Royal Saudi Air Force have always operated the Tornado F3 ("ADV" in RSAF parlance) since 1989 with Automatic Wing Sweep enabled - the system was indeed certified for use - it has proved highly reliable in use and has saved many a pilot from overstressing an aircraft.....

soddim
5th Aug 2008, 12:45
Not to mention the number of times auto wing sweep has resulted in a safe pull-out from that sinking feeling!

threeputt
5th Aug 2008, 16:35
The F 111 WS lever is nothing like the GR/4. It had a F*7k off lever just under the canopy rail on the left hand side.

On my one and only sortie as a TACEVAL chase I was amazed to watch as my "stick monkey" operated it: as I remember it had about a 4 foot travel and it appeared to be a bit of a strain as he had to dislocate (sic) his shoulder or change hands to get it to the fully "aft" (72) position!

May 18 1988-Upper Heyford TACEVAL (CLSP launch) 50th TFS,airframe UH 006, Capt Carpenter-2.05.

It also had a less than intuitive method of fixing the radar/nav kit....not being particularly intuitive I never fixed it!

Fine aircraft all the same, especially above 600kts!

3P:ok:

ARINC
5th Aug 2008, 21:51
Just don't try sweeping Tornado wings when on jacks with the flaps down......:\

L J R
6th Aug 2008, 02:30
3 Putt, there are two settings in the F-111 wingsweep. 16 for TO/Land and 72 for cruise. The rest is for whimps!

Jaysi
6th Aug 2008, 03:55
Airborne, the F14 wingsweep had both automatic and manual options. The mode was selected via a button on the inboard throttle; selecting up (if my memory serves me right...could be down) was auto whereby the wings moved as a function of mach number. When in the neutral position the same electronically actuated switch moved the wings forward and back as per the Tornado. In manual you could not override the mach number programming or "overstress" the wings...ie have them too far forward for the mach number. You could, however, manually sweep them all the way back whilst below the programmed mach number to look cool on the break as was the SOP (who was I too argue). The effect produced excellent vapour off the wings whilst pulling hard fully swept at 350 kts at full throttle (similar to lightning rotation take off). The jet had no SPILS (spin prevention incidence limiting system) as per the Tornado, so had to be handled carefully as the "alpha" built up rapidly. The aim was to bleed down to gear speed rolling out downwind, then put the wings forward whilst level...all good fun (and on Youtube fighter fling video).

The "handle" (used primarily on the ground) was, similarly to the Tornado, on the cockpit left hand side. It had a flat top and was recessed under a "cover" which could be lifted out of the way for operation on the ground. When recessed, the bottom of the handle, now below the panel, locked into a "cam" which connected to the switch server on the throttle and therefore to the wing motor mechanism. On the ground the wings had an "oversweep" position to save room on the carrier deck whereby the wings were pulled back overlapping the horizontal tailplane. In order to get into oversweep, you raised the handle cover and pulled the handle upwards and out of the "cam" (light came on). Then you physically pulled the handle back until a first rearward position where the tailplane was in the way. The jet sensed this and you had to move the tailplane out of the way, the handle no longer resisted the movement and went back a further inch or two into oversweep. The handle could then be pushed back down into its housing.

Hope all that makes sense. Sorry I got carried away with the earlier nostalgia...

Lima Juliet
6th Aug 2008, 20:11
AWS was removed from the "Tonka" on the advice from the nerds at Boscombe. It's hardly surprising that a 5000hr TP could do better manually than the AWS in normal aerobatic manoeuvres...however, in the hands of Rodney F@cknuckle with 50hrs on type, in ACT, it would have been great! Still, it gave the Nav a chance to shout "Wings" at Biggles with delightful glee everytime the wings were in the wrong place. This was later qualified with "Wings Forward/Back" when the previous "Wings" call made Rodney F@cknuckle move his 45deg wings forward when supersonic and overstressing the jet! :ugh:

LJ

advocatusDIABOLI
6th Aug 2008, 20:21
ARINC,

what about the mechanical interface between the Flap Lever, and the Wing Sweep Lever? Was that broken or disconnected? You can't (Normally) move the wings lever if the flaps are down. Man'vres automatically retract tho.

Advo

ARINC
6th Aug 2008, 20:25
ARINC,

what about the mechanical interface between the Flap Lever, and the Wing Sweep Level? Was that broken or disconnected? You can't (Normally) move the wings level if the flaps are down. Man'vres automatically retract tho.

Advo

Yes it was disconnected.....Aircraft on Major servicing St.Athan red faces all round.

advocatusDIABOLI
6th Aug 2008, 20:27
Leon,

Normal answer to 'wings!' is "Yeh, Scan Up/down!"

Hope that brought back some memories, from you better 'tumbleweed' days.

Advo

Lima Juliet
6th Aug 2008, 21:33
Devil's Advocate

Scan Up/down

Now you are showing your age - from the mid-to-late nineties this was an automatic function giving Navs even more chance to notice the wings were in the wrong place :p

By the way

the wings can be swept to any postion, but normally used in 25(forward) 45 (1/2) or 63/67(back)

it is also a shame that the "Fin" was never cleared for all sweeps as Barnes Wallis had intended with his Variable Geometry concept. Did you ever watch the SEP bars move above the horizon when you moved the wings between 25 and 45 at high subsonic cruise at medium to high level (well high for a Tonka!) - the TPs and Eng Authority have a lot to answer to! :ugh:

I here you on 35wg, though :ok:

LJ

soddim
6th Aug 2008, 22:12
I will never understand the rationale that does not allow the use of intermediate wing sweep angles on the Tornado. If the intermediate positions are not cleared for flight then, QED, it should not be permitted to move the wings in flight because the jet still flies while the wings are moving through the intermediate positions. Surely it is not beyond safe interpolation to issue conservative clearances for intermediate wing sweeps?

Lima Juliet
6th Aug 2008, 22:16
A very valid point Reg...

artyhug
6th Aug 2008, 23:07
Which is why there are indeed limited clearances for 35 and 58 wg. Of course if your left hand is as slow to respond to nerve impulses as mine can be you often find the wings sweep evvvvvvveeeeeeerrrrrr so slowly, so slowly in fact that they seem to not be moving at all......

;)

advocatusDIABOLI
7th Aug 2008, 06:35
Leon,

You are ofcourse right. About intermediate wing sweeps. My undertsanding was that it was more to do with fatigue management, as the readings were only taken at certain wing sweeps (25,45,58,63,67).

SEP bar management on long transits did offer some good fuel savings / speed for Mach / Alt.

But overall, I like a bigger wing, lower loading and more thrust. Bit like Typhoon really! :ok:

Advo

soddim
7th Aug 2008, 13:09
Unfortunately one effect of not clearing fully all the available wing sweep positions led indirectly to the lack of auto wing sweep in the RAF. The problem was that the automatic schedule shaved off some corners of the performance envelope in order to ensure that wings reached the required sweep within the mach/airspeed limitations - and, when sweeping commenced, no other angle could be selected until the required setting was achieved. Although manual wing sweeping should also be performed in the same way, in practise pilots frequently do not anticipate and also change their selection in mid sweep contrary to the R to S.

It was thought that a competent pilot could do better than the automatic schedule but in practise this is simply not the case because the pilot has other more important priorities and frequently operates the jet at less than the optimum sweep angles and in excess of normal operating limits.

To those proponents just a few set sweep angles I would add that an aircraft like the Tornado can perform well as a bomber with just a few settings but it needs all the manoeuvring help it can get in the fighter role - even with AMRAAM and ASRAAM. With fully variable auto wing sweep and manoevres it would be a lot better off - and this could have been a no-cost option for the RAF. In Saudi service the auto wing sweep and manoeuvres on the fighter have proved their worth - fully variable would be even better.