LYNX main servo valve seizure
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LYNX main servo valve seizure
Heared rumours off a British Lynx over London loosing 300 feet during a main servo valve seizure in roll.Was it the new actuators or the old servos??
Also heard that it was the left seater that switch off the appropiate hyd. system??? Any rumors .....
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It was the old pre-mod 793 servos which have since been replaced in this specific aircraft! And yes it was the left hand seat that flipped the hyd 1 switch as the handling pilot had the vulcan death grip on the collective at the time! Thank heavens it was at 1000' and not low level.
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A change off underwear would be in order!!
Nice job of the LHS!!Did the cyclic actualy move in the direction off the main servo valve seizure in roll?
As fare as I know this is one off the first seizures that the crew actualy lived to tell the story, well done!!!
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Thanks for the info!!!
PONTCIVVY is it possible to get a copy off the incedent report??
I am always looking for information from the real world to check if the simulation world is doing it correct!!
PONTCIVVY is it possible to get a copy off the incedent report??
I am always looking for information from the real world to check if the simulation world is doing it correct!!
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Probably a bit late in the day to investigate failure trends now on the Lucas Servo. DARA Almondbank were/are the 4th line service unit and have ALL the overhaul/repair records, going back to serial No1, in their very dusty archive.
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Just for information there are nations outside GB who is going to fly LYNX for some years to come ie with the old servo!!
This malfunction being one off the rear ones we should try to gain the most off it
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The incident signal was circulated around the Lynx fleet within British forces, I am afraid that I don't have one to hand but it does not really shed much more light on the matter.
Lynx at 1000' over the Lee valley waiting to enter the heli lanes and initiating a right hand turn to orbit whilst waiting for clearnace from Thames Radar. LHS was minding his own business lokoing at the maps for the next lane. When he noticed that the AOB was exceeding 40 degrees or so he looked towards the RHS as if to say 'cut that out!', or words to that effect! It was then that the RHS declared a hydraulics malfunction and LHS immediately de-selected the Hyd 1. Recovery was not an instantaneous jerk but a gradual one. Height loss was 300', AOB was in excess of 70 degrees and it had turned through 180 degrees.
Urgency declared and recovered to nearby Stapleford due to built up areas and nature of terrain.
The cyclic was continuing to ramp over to the right and the RHS insists that there was absolutely nothing that he could do about it, despite his best efforts!
The investigation was delayed for a few months as it went straight to Fairoaks for a mod. Cause was not identified although the servos were replaced with Faireys.
All good stuff. There is one thing you can guarantee with the widow maker, it will keep you on your toes!
Lynx at 1000' over the Lee valley waiting to enter the heli lanes and initiating a right hand turn to orbit whilst waiting for clearnace from Thames Radar. LHS was minding his own business lokoing at the maps for the next lane. When he noticed that the AOB was exceeding 40 degrees or so he looked towards the RHS as if to say 'cut that out!', or words to that effect! It was then that the RHS declared a hydraulics malfunction and LHS immediately de-selected the Hyd 1. Recovery was not an instantaneous jerk but a gradual one. Height loss was 300', AOB was in excess of 70 degrees and it had turned through 180 degrees.
Urgency declared and recovered to nearby Stapleford due to built up areas and nature of terrain.
The cyclic was continuing to ramp over to the right and the RHS insists that there was absolutely nothing that he could do about it, despite his best efforts!
The investigation was delayed for a few months as it went straight to Fairoaks for a mod. Cause was not identified although the servos were replaced with Faireys.
All good stuff. There is one thing you can guarantee with the widow maker, it will keep you on your toes!
The new servos are all very well. You can "break" through the restriction and regain control. However, you have no idea which is the faulty hydraulic system, and the same thing can happen again at any time. 
