Chinook Question
Join Date: Sep 2005
Location: Notts
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Short Cut
Well it sounds like you're spending too much time in the Waltham Abbey Area!
It also happens to be one of the exit routes from the London CTR for Wokkas that have taken the "short cut" across The Smoke from their base in Hants.
It also happens to be one of the exit routes from the London CTR for Wokkas that have taken the "short cut" across The Smoke from their base in Hants.
Join Date: Dec 1999
Location: UK
Posts: 2,584
Likes: 0
Received 0 Likes
on
0 Posts
Could be on a Navex route. I have Chinooks, Apaches and the occasinal Lynx passing my place regularly, all on the same route and almost always in the same direction. It is not on any obvious direct between stations or avoiding other airspace so conclude nav route.
So here's another Chinook question (could be applied to Lynx as well):
Why can I hear a Chinook/Lynx approaching from miles away but, once they have flown over me, the sound fades quite rapidly? In other words, I can hear a Chinook coming towards me from about 2 miles away, but can't hear it going away from me beyond about half a mile.
Obviously wind direction will have some effect but this is too regular to be just down to wind. I think it applies to all helicopters but it is far more noticeable for the distinctive sound of the Chinook and Lynx.
Why can I hear a Chinook/Lynx approaching from miles away but, once they have flown over me, the sound fades quite rapidly? In other words, I can hear a Chinook coming towards me from about 2 miles away, but can't hear it going away from me beyond about half a mile.
Obviously wind direction will have some effect but this is too regular to be just down to wind. I think it applies to all helicopters but it is far more noticeable for the distinctive sound of the Chinook and Lynx.
Join Date: Aug 2007
Location: CT
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
The short answer is that noise propagation from a rotor in forward flight is highly asymmetric. The reason for this is "thickness" noise generated by the advancing blades which propagates primarily in the direction of travel. This google search would be the place to start for the long answer. http://www.google.com/search?hl=en&s...ss&btnG=Search