Question for the helicopter fans???

The other day one of the police departments that I work with mentioned that
another PD aviation section had an "overspin" on their helicopter.. I was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...

Many thanks,

Andrew

"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com wrote in
message ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...



Rotor RPM limit exceeded.


Luke

"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com wrote in
message ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...



Rotor RPM limit exceeded.


Luke

"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com skrev i
en meddelelse ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...

I'll venture a guess:
The rotor presumably has a maximum rpm. It is possible to overspin the rotor
if you decend very rapidly . .
A Police-helicopter can do that when they decend to check occupants in cars
they are persuing - or if they have an engine failure, in which case you
spin-up the rotor during the decend to make sure you have lift enough for
the landing.
It's called "autorotation" - I've tried it as a passenger in a Hughes OH-6
during a training flight, pretty scary.


Regards Alf

"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com skrev i
en meddelelse ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...

I'll venture a guess:
The rotor presumably has a maximum rpm. It is possible to overspin the rotor
if you decend very rapidly . .
A Police-helicopter can do that when they decend to check occupants in cars
they are persuing - or if they have an engine failure, in which case you
spin-up the rotor during the decend to make sure you have lift enough for
the landing.
It's called "autorotation" - I've tried it as a passenger in a Hughes OH-6
during a training flight, pretty scary.


Regards Alf

Many thanks...

Alf

"alf blume" wrote in message
. ..

"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com skrev
i en meddelelse ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I
was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...

I'll venture a guess:
The rotor presumably has a maximum rpm. It is possible to overspin the
rotor if you decend very rapidly . .
A Police-helicopter can do that when they decend to check occupants in
cars they are persuing - or if they have an engine failure, in which case
you spin-up the rotor during the decend to make sure you have lift enough
for the landing.
It's called "autorotation" - I've tried it as a passenger in a Hughes
OH-6 during a training flight, pretty scary.


Regards Alf

Many thanks...

Alf

"alf blume" wrote in message
. ..

"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com skrev
i en meddelelse ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I
was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...

I'll venture a guess:
The rotor presumably has a maximum rpm. It is possible to overspin the
rotor if you decend very rapidly . .
A Police-helicopter can do that when they decend to check occupants in
cars they are persuing - or if they have an engine failure, in which case
you spin-up the rotor during the decend to make sure you have lift enough
for the landing.
It's called "autorotation" - I've tried it as a passenger in a Hughes
OH-6 during a training flight, pretty scary.


Regards Alf

G'day All,

this occurs only if the main rotor blades are not correctly aligned &
tracked - I have had it occur once when after many hours of boring
tracking - i.e. they put strobe reflecting bits on the end of the blades -
for say a 3 bladed job the strobe thingos are sorta like this - | _ / - you
as a pilot pull it into a 3' hover & hold it - the maintenance bloke aims
his strobe gun on the main rotors usually sitting on the top of a ladder -
notes stuff arcane stuff in his little book - sees which one of the 3 is
higher or lower. Then we land the helicopter - shut it down & the LAME makes
adjustments to all the nuts & bolts on the main rotor hub & the process is
repeated - sometimes for an agonising period.

Then ya go out & fly it - with the LAMe sitting in with ya - you then put it
into an autorotation & if the blades have been tracked successfully then the
main rotor RPM should stabilise at the max RPM red line.

So I suppose what I am trying to say is that if you experience a main rotor
overspeed then the maintenance of the machine is a bit of a worry. I still
have the bolt that was removed from the offending blade - it was cracked all
the way through - so it is really a very serious problem to experience a
main rotor overspeed.

see ya

Conscious Pilate

P.S. Your total logged time for about 3 hrs work is usually about 15mins!!

G'day All,

this occurs only if the main rotor blades are not correctly aligned &
tracked - I have had it occur once when after many hours of boring
tracking - i.e. they put strobe reflecting bits on the end of the blades -
for say a 3 bladed job the strobe thingos are sorta like this - | _ / - you
as a pilot pull it into a 3' hover & hold it - the maintenance bloke aims
his strobe gun on the main rotors usually sitting on the top of a ladder -
notes stuff arcane stuff in his little book - sees which one of the 3 is
higher or lower. Then we land the helicopter - shut it down & the LAME makes
adjustments to all the nuts & bolts on the main rotor hub & the process is
repeated - sometimes for an agonising period.

Then ya go out & fly it - with the LAMe sitting in with ya - you then put it
into an autorotation & if the blades have been tracked successfully then the
main rotor RPM should stabilise at the max RPM red line.

So I suppose what I am trying to say is that if you experience a main rotor
overspeed then the maintenance of the machine is a bit of a worry. I still
have the bolt that was removed from the offending blade - it was cracked all
the way through - so it is really a very serious problem to experience a
main rotor overspeed.

see ya

Conscious Pilate

P.S. Your total logged time for about 3 hrs work is usually about 15mins!!

Aree on the Rotor RPM limit exceeded.


But practice autos are a kick in the ass for fun. Best e ticket ride
you can ge as a helo crewman.




On Sun, 10 Dec 2006 10:10:45 +0100, "alf blume"
wrote:


"Andrew-S" I-Still-Hate-Spammers@Sorry-I had-to-leave-for-bit.com skrev i
en meddelelse ...
The other day one of the police departments that I work with mentioned
that
another PD aviation section had an "overspin" on their helicopter.. I was
going to ask at the time what an overspin was but I forgot... So my
question is what exactly is an overspin??? I checked the web and the
answers I found where not exactly enlightening...

I'll venture a guess:
The rotor presumably has a maximum rpm. It is possible to overspin the rotor
if you decend very rapidly . .
A Police-helicopter can do that when they decend to check occupants in cars
they are persuing - or if they have an engine failure, in which case you
spin-up the rotor during the decend to make sure you have lift enough for
the landing.
It's called "autorotation" - I've tried it as a passenger in a Hughes OH-6
during a training flight, pretty scary.


Regards Alf