Gazelle: Flying, operating, buying
Cyclic back/collective up....cows get smaller
Cyclic forward/collective down....cows get bigger
What more do you need?
Cyclic forward/collective down....cows get bigger
What more do you need?
Well RougeTrooper,
I´ve found some old - very old pages from my course at Culdrose...
https://www.dropbox.com/s/f9plh4tuhy...20MK2.pdf?dl=0
which might be helpful.
The pdf might get deleted when I need the space - so if you find it useful, save it ;-)
To the SAS - as far as I remember, it kicked in at something around 40 knots IAS, which could be felt as a slight jolt, if you weren´t flying properly.
Into the course I really didn´t thought about any more....
Was a really nice bird to fly :-)
I´ve found some old - very old pages from my course at Culdrose...
https://www.dropbox.com/s/f9plh4tuhy...20MK2.pdf?dl=0
which might be helpful.
The pdf might get deleted when I need the space - so if you find it useful, save it ;-)
To the SAS - as far as I remember, it kicked in at something around 40 knots IAS, which could be felt as a slight jolt, if you weren´t flying properly.
Into the course I really didn´t thought about any more....
Was a really nice bird to fly :-)
The SAS yaw channel disengaged at 40 kts during acceleration to forward flight.
It was there to reduce 'twitchiness' in the hover or at low speeds and wasn't needed at higher speeds as the wing-like tail provided adequate damping.
It was there to reduce 'twitchiness' in the hover or at low speeds and wasn't needed at higher speeds as the wing-like tail provided adequate damping.
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But since using the SAS is just cheating I've not experienced it in a while. Lovely aircraft
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Hey 500 Y SAS is a md thing for the 520 or 600
SAS was what the uk mil put on their gazelles a bit like stabilisers on a kids bike
When the army men started flying the gazelles the army didn't have it put in theirs they didn't need it
SAS was what the uk mil put on their gazelles a bit like stabilisers on a kids bike
When the army men started flying the gazelles the army didn't have it put in theirs they didn't need it
Army didn't get it cause they break all their stuff 😜
Sophisticated equipment needs tender careing pilots! 😉
The Army Gazelle fleet included the aircraft for the Royal Marines (3 Brigade Air Squadron as was).
The RM Gazelles had SAS fitted presumably for reduced workload on over water ops.
The RAF and RN training Gazelles all had SAS fitted but the Army probably paid extra to have theirs removed.
Given the roles that some of the AAC ones had (lots of very high hovering) SAS would have been a really good idea.
Flown both and would opt for SAS every time but probably without the yaw channel selected in.
There is a school of thought that the yaw SAS can hide the real pedal position required because it moves the actuator while the pedals remain where they are - then, when the actuator runs out of authority, the aircraft starts to yaw but with the pedal position already lagging behind where it needed to be.
The result was that a large right pedal input was required to stop the yaw which many pilots were reluctant to apply so the rate of yaw increased. Some believed they had experienced a TR drive failure when all they needed was full right pedal.
Thus the myth of Fenestron Stall was born.
The RM Gazelles had SAS fitted presumably for reduced workload on over water ops.
The RAF and RN training Gazelles all had SAS fitted but the Army probably paid extra to have theirs removed.
Given the roles that some of the AAC ones had (lots of very high hovering) SAS would have been a really good idea.
Flown both and would opt for SAS every time but probably without the yaw channel selected in.
There is a school of thought that the yaw SAS can hide the real pedal position required because it moves the actuator while the pedals remain where they are - then, when the actuator runs out of authority, the aircraft starts to yaw but with the pedal position already lagging behind where it needed to be.
The result was that a large right pedal input was required to stop the yaw which many pilots were reluctant to apply so the rate of yaw increased. Some believed they had experienced a TR drive failure when all they needed was full right pedal.
Thus the myth of Fenestron Stall was born.
Fenestron stall?
Reading PPRune talk about fenestron stall I have often wondered why none of us on the Gazelle IFTU encountered it, and I have no memory of any SAS in any of the aircraft (all Army except one RN I think). I guess that last sentence by Crab explains it now.
Hi,
Well, there are still pilots around, which don' t understand how thrust on a fenestron differs to thrust on an conventional tail rotor.
Airbus helicopers has graphs and a handout stating, that right pedal use may need longer travel - up to full right pedal- to stop yaw.
The earlier applied- the better!!!
If you understand that and fly accordingly, you won't get caught by surprise!
Well, there are still pilots around, which don' t understand how thrust on a fenestron differs to thrust on an conventional tail rotor.
Airbus helicopers has graphs and a handout stating, that right pedal use may need longer travel - up to full right pedal- to stop yaw.
The earlier applied- the better!!!
If you understand that and fly accordingly, you won't get caught by surprise!
FB - yes, the Airbus safety notice highlights also how the thrust from a fenstron doesn't change in a linear fashion with pedal position, it is more of an S shaped line on the graph. I think it has to do with the airflow around the duct which can provide additional anti-torque lift in some conditions.
I think this is why that kick in yaw you described earlier occurs when the SAS channel drops out at 40 kts - combined with the actuator effect I mentioned.
I think this is why that kick in yaw you described earlier occurs when the SAS channel drops out at 40 kts - combined with the actuator effect I mentioned.
Reading PPRuNe talk about fenestron stall I have often wondered why none of us on the Gazelle IFTU encountered it,
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Never perform autorotation with GZL ? Best time to understand the fenestron effect Specially when crosswind 
NB : In the French Army all 341 have a SAS, same kind on the AL 3
All of the 342 have a 2 axis autopilot.
Specially when crosswind NB : In the French Army all 341 have a SAS, same kind on the AL 3
All of the 342 have a 2 axis autopilot.
Not so much the fenestron effect, just the effect of that big tail fin with a crosswind on autos.
Not unusual to run out of left pedal on an EOL - as the Nr decays, the thrust from the fenstron drops off very quickly.
Not unusual to run out of left pedal on an EOL - as the Nr decays, the thrust from the fenstron drops off very quickly.
I´ve found some old - very old pages from my course at Culdrose...
https://www.dropbox.com/s/f9plh4tuhy...20MK2.pdf?dl=0
which might be helpful.
The pdf might get deleted when I need the space - so if you find it useful, save it ;-)
Was a really nice bird to fly :-)
https://www.dropbox.com/s/f9plh4tuhy...20MK2.pdf?dl=0
which might be helpful.
The pdf might get deleted when I need the space - so if you find it useful, save it ;-)
Was a really nice bird to fly :-)