Any Typhoon pilots?
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If only I could remember. I will research, however, I do recall that there were square select buttons, I believe near the throttles. The system could be selected to be in full auto AWS and AMD or just auto AWS. Manual selection of either AWS or AMD deselected that part of the system.
The downfall of the AWS was that only 25/45/58/67 were in the programme so it was not fully variable. The AMD operated on AOA values. It could not anticipate manoeuvre and because the srew jacks took so long to operate, they could not cater for the rapid onset of AOA and so performance was less than optimal. When flying a non aerodynamic brick this was not on ideal situation.
The downfall of the AWS was that only 25/45/58/67 were in the programme so it was not fully variable. The AMD operated on AOA values. It could not anticipate manoeuvre and because the srew jacks took so long to operate, they could not cater for the rapid onset of AOA and so performance was less than optimal. When flying a non aerodynamic brick this was not on ideal situation.
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Flew the F3 or ADV as was named there with RSAF and it was superb. Made it just like flying a big hawk.
Disabled if for close formation and landing.
Whoever was responsible for the call not to enable it for the RAF was a donkey.
Button for on/off was next to your left thigh-old age, and too many type changes inbetween preclude any more detail.
Disabled if for close formation and landing.
Whoever was responsible for the call not to enable it for the RAF was a donkey.
Button for on/off was next to your left thigh-old age, and too many type changes inbetween preclude any more detail.
Last edited by spoff; 6th Oct 2012 at 06:23.
Ecce Homo! Loquitur...
Am I wrong in recallng that one of the main reasons for disabling the F3 autosweep was fatigue.
The initial assumption was that the F3 would generate less fatigue than the GR1; however when they wired one up and did tests it was dramatically higher*. Specifically, it spiked and went through the roof when the wings swept when pulling G.
So the system was disabled and the brief was to sweep before or after, but not during, the turn........
(*The assumption being that the GR1 at low level would suffer more, but in fact the carried stores and majority of flight wing swept kept it in a benign regime. The F3 constantly thrashing the wings back and forth with no tanks was much worse. At which stage they introduced a test rig and ran it to keep ahead of the fleet; which lead to one FI programme after another to fix things as more bits fell off.
I did hear the story that the final life of the airframe was determined when the test item "disintegrated catastrophically" in the rig. But that was possibly anecdotal.)
The initial assumption was that the F3 would generate less fatigue than the GR1; however when they wired one up and did tests it was dramatically higher*. Specifically, it spiked and went through the roof when the wings swept when pulling G.
So the system was disabled and the brief was to sweep before or after, but not during, the turn........
(*The assumption being that the GR1 at low level would suffer more, but in fact the carried stores and majority of flight wing swept kept it in a benign regime. The F3 constantly thrashing the wings back and forth with no tanks was much worse. At which stage they introduced a test rig and ran it to keep ahead of the fleet; which lead to one FI programme after another to fix things as more bits fell off.
I did hear the story that the final life of the airframe was determined when the test item "disintegrated catastrophically" in the rig. But that was possibly anecdotal.)
Last edited by ORAC; 10th Oct 2012 at 12:01.
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I was the Sqn Fatigue officer for a while.
Sounds like a very tiring job!
Sorry, I'll get my coat!
Sounds like a very tiring job!
Sorry, I'll get my coat!
Last edited by Out Of Trim; 10th Oct 2012 at 16:43.
ORAC,
Mostly right, but the reasons for this were interesting (to say the least). Using the wing sweep (auto or manual), which one has/had to, would take the aircraft through an astonishing number of defined limitations (speed, normal g, aoa and rolling limits). The aircraft could only record consumed FI at set points and (we all know) the computer(s) didn't have the capacity to interpolate between these points. In truth, no one really knew what happened anyway, because the testing on the fatigue model was still running (obviously).
The apparent fatigue consumption as recorded by the fatigue meter didn't match what was really happeneing (as we discovered when they opened them up for the first time) AND the assumptions about how the F would burn FI compared to the GR were based on a fictitious interceptor role; we then went on to do loads of low level and a lot of 'high' g manouvring that wasn't 'expected'.
As far as I know, there was no significant FI penalty in moving the wings under normal g - there would have been yet another set of endless NO and NE limits for that if there were.
The issue with AWSMDS wasn't one of fatigue. It was, I am convinced, to do with clearances and money.
IMHO.
Courtney
Mostly right, but the reasons for this were interesting (to say the least). Using the wing sweep (auto or manual), which one has/had to, would take the aircraft through an astonishing number of defined limitations (speed, normal g, aoa and rolling limits). The aircraft could only record consumed FI at set points and (we all know) the computer(s) didn't have the capacity to interpolate between these points. In truth, no one really knew what happened anyway, because the testing on the fatigue model was still running (obviously).
The apparent fatigue consumption as recorded by the fatigue meter didn't match what was really happeneing (as we discovered when they opened them up for the first time) AND the assumptions about how the F would burn FI compared to the GR were based on a fictitious interceptor role; we then went on to do loads of low level and a lot of 'high' g manouvring that wasn't 'expected'.
As far as I know, there was no significant FI penalty in moving the wings under normal g - there would have been yet another set of endless NO and NE limits for that if there were.
The issue with AWSMDS wasn't one of fatigue. It was, I am convinced, to do with clearances and money.
IMHO.
Courtney
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I wasn't actually involved at the time but I was told later that the reason in post #19 by Dominator2:
"As Fred did not trust anything automatic, he moved the wings and slats manually, but without the system disabled. Within a couple of weeks the jets were grounded as the follow-up motors were screwed (a technical term)."
...is closer to the mark. As confirmation its worth noting the Saudi ADVs had no issues with AWS as the default option.
"As Fred did not trust anything automatic, he moved the wings and slats manually, but without the system disabled. Within a couple of weeks the jets were grounded as the follow-up motors were screwed (a technical term)."
...is closer to the mark. As confirmation its worth noting the Saudi ADVs had no issues with AWS as the default option.
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Courtney,
You are correct to say that the issue with AWSMDS wasn't one of aircraft fatigue although it was to do with the fatigue or failure or the followup system. AWS was not designed to be manually over-riden. The systems engineers at Warton had no concept that a pilot would wish to move the wings manually. Also, there was a belief that a pilot would never use an intermediate wing aweep setting since they were not cleared for service. The system failed to come into service in the RAF due to a lack of knowledge at middle management. As mentioned, the RSAF operated the system throughout the life of the aircraft without problem.
The story of the aircraft fatigue is a different one. The fatigue was recorded at the different wing settings and at certain G. The factoring to ascertain the total aircraft fatigue was based on the profiles in the Statement Of Operating Intent. Engineers believed that these profiles were accurate and aircrew could not be bothered with it. At the end it was very simplistic and was like trying to crack a walnut with a sledge hammer.
You are correct to say that the issue with AWSMDS wasn't one of aircraft fatigue although it was to do with the fatigue or failure or the followup system. AWS was not designed to be manually over-riden. The systems engineers at Warton had no concept that a pilot would wish to move the wings manually. Also, there was a belief that a pilot would never use an intermediate wing aweep setting since they were not cleared for service. The system failed to come into service in the RAF due to a lack of knowledge at middle management. As mentioned, the RSAF operated the system throughout the life of the aircraft without problem.
The story of the aircraft fatigue is a different one. The fatigue was recorded at the different wing settings and at certain G. The factoring to ascertain the total aircraft fatigue was based on the profiles in the Statement Of Operating Intent. Engineers believed that these profiles were accurate and aircrew could not be bothered with it. At the end it was very simplistic and was like trying to crack a walnut with a sledge hammer.
No need for slats at landing.
These create a powerful nose-down pitching moment which may be offset somewhat by the nose-up pitching moment caused by slats.
Don't know about the Tornado, having not flown it.
I think the thread is slightly confused, the point was about Typhoon's slats and that, of course has socking great canards to control the pitching moment. Tornado needs all the 'high lift devices' it can muster for landing.
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It is difficult to believe that Tornado F3, in 25 wing, full flap and slat landed nearly 20 kts faster than the F4. Due to it being a screwed up mod of a GR1 if you landed slower you could run out of pitch control. I remember that a TP tried and ended up heavy landing.
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",,,socking great canards to control the pitching moment..."
I believe that while the foreplanes are used in starting and stopping manoeuvres they're not sized as conventional control surfaces – compare the FP size to Tornado tailplanes and note the shorter lever arm to the cg. Once the manoeuvre is initiated the foreplanes are used to trim in pitch and enable the flaperons to operate in the middle of their range of movement at all incidences. This way the flaperons shouldn't get too close to saturation (hitting the end stops) and losing pitch control/damping. This also assures plenty of roll control/damping at all incidences. I was once told that for a delta wing, starting the roll is easy, stopping it was the hard part.
I believe that while the foreplanes are used in starting and stopping manoeuvres they're not sized as conventional control surfaces – compare the FP size to Tornado tailplanes and note the shorter lever arm to the cg. Once the manoeuvre is initiated the foreplanes are used to trim in pitch and enable the flaperons to operate in the middle of their range of movement at all incidences. This way the flaperons shouldn't get too close to saturation (hitting the end stops) and losing pitch control/damping. This also assures plenty of roll control/damping at all incidences. I was once told that for a delta wing, starting the roll is easy, stopping it was the hard part.
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Lightning Mate,
what I meant is, slat as such won't add any lift to the Typhoon.
Since I never saw Typhoon deploying flaperons on approach, the FCS may just as well stow the slats, too.
what I meant is, slat as such won't add any lift to the Typhoon.
Since I never saw Typhoon deploying flaperons on approach, the FCS may just as well stow the slats, too.
EAP86,
Well put, but have you seen where the limit of travel is on those big boys? I think the difference is in the effect foreplanes have on pitch vs that of tail planes - dynamically stable vs unstable. And you are absolutely right, even more so in pitch with canards; starting the pitch is easy...
Well put, but have you seen where the limit of travel is on those big boys? I think the difference is in the effect foreplanes have on pitch vs that of tail planes - dynamically stable vs unstable. And you are absolutely right, even more so in pitch with canards; starting the pitch is easy...