Rotor blade stall
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I think one of the issues we had in the early days of the MK 8 was the absence of any ODM's! The aircraft came with a MTOW of 5300Kg IIRC and the performance data we had was from the Lynx Mk 3 S Gulf Mod which had a MTOW of 4800Kg.
Got to love the MOD's shortcuts!
(sorry if figures are out, memory is going back to the 90's!)
Got to love the MOD's shortcuts!
(sorry if figures are out, memory is going back to the 90's!)
I have 4875Kg as a memory for the Mk 7 (also in the 90s).
Interesting that the RN allowed the display manoeuvres because the AAC ones had G meters fitted, all the manoeuvres were flown on a fully instrumented aircraft at Westlands and there were large fatigue/servicing penalties for each display manoeuvre.
I flew the 90/90 roll a few times without 'jackstall' and all the displays were done with pitch and roll AP lanes out (since the gyros would topple anyway) but retaining yaw channel. There was also a 140Kt IAS limit as it was the VL for the TOW booms.
I still don't believe RBS or jackstall are possible in that aircraft - the back flip hover to hover from 1000' to 700' was a 3 G manoeuvre no matter how carefully it was flown and it was good as gold.
I don't know of any AAC Lynx display pilot who has been 'flicked out' of a manoeuvre although the Eagle Roll was a tricky one to get right.
Unusual to have a problem in a vertical dive, even with a rapid roll, but the speed does increase very quickly in that configuration, especially without the drag of the TOW booms.
A rapid right roll at high IAS would give the advancing blade a much higher AoA than normal, perhaps it was high-speed stall that caused the problem.
Interesting that the RN allowed the display manoeuvres because the AAC ones had G meters fitted, all the manoeuvres were flown on a fully instrumented aircraft at Westlands and there were large fatigue/servicing penalties for each display manoeuvre.
I flew the 90/90 roll a few times without 'jackstall' and all the displays were done with pitch and roll AP lanes out (since the gyros would topple anyway) but retaining yaw channel. There was also a 140Kt IAS limit as it was the VL for the TOW booms.
I still don't believe RBS or jackstall are possible in that aircraft - the back flip hover to hover from 1000' to 700' was a 3 G manoeuvre no matter how carefully it was flown and it was good as gold.
I don't know of any AAC Lynx display pilot who has been 'flicked out' of a manoeuvre although the Eagle Roll was a tricky one to get right.
Unusual to have a problem in a vertical dive, even with a rapid roll, but the speed does increase very quickly in that configuration, especially without the drag of the TOW booms.
A rapid right roll at high IAS would give the advancing blade a much higher AoA than normal, perhaps it was high-speed stall that caused the problem.
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Only ever happened the once and then I, understandably, modified the display routine. We were never allowed to do the 'backflip', or indeed a barrel roll as our aircraft were never fitted with the inverted capable oil system AFAIK.
No G meters fitted either. Mind you we probably would have broken them during deck ops! One of the best helicopters I had the privilege to fly, the Lynx.
No G meters fitted either. Mind you we probably would have broken them during deck ops! One of the best helicopters I had the privilege to fly, the Lynx.
One of the best helicopters I had the privilege to fly, the Lynx.
One of the best helicopters I had the privilege to fly, the Lynx.
Proof, if proof were needed, of the value of 'development' ! When they first arrived at Boscombe. their major notable features were the necessiity for Fire truck attendance at start and shut-down, (oil residue) and the ability to distribute rotor-tip weights around the airfield!. The high speed run pitch-overs produced smoke belches akin to a worn-out 'banker' on the Lickey incline!
Proof, if proof were needed, of the value of 'development' ! When they first arrived at Boscombe. their major notable features were the necessiity for Fire truck attendance at start and shut-down, (oil residue) and the ability to distribute rotor-tip weights around the airfield!. The high speed run pitch-overs produced smoke belches akin to a worn-out 'banker' on the Lickey incline!
CJ - that reminded me of the 'modification' that was a little can hung off the back end of the jet pipe to collect all the oil dripping out of it after shutdown.
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The well known 'Labyrinth Seal' on the Gem. As my SMR used to say, 'if it ain't leaking it's empty boss'. I seem to remember they even welded a flange with a small hole the right diameter for a wire coat hangar onto the bottom of the exhaust!
As a kid growing up in Tardebigge, between Redditch and Bromsgrove, my mate and I often used to cycle over to the Hewel Lane bridge to watch the bankers shoving the trains up the incline! Ahhhhh..... the memories come flooding back!
As a kid growing up in Tardebigge, between Redditch and Bromsgrove, my mate and I often used to cycle over to the Hewel Lane bridge to watch the bankers shoving the trains up the incline! Ahhhhh..... the memories come flooding back!
