Why angled/tilted tail rotors?
Joined: Jul 2002
Aviation Qualifications: ATPL(H)
Posts: 3,052
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From: UK
It creates a little bit of vertical lift. (I can't remember exactly how much but I think it's in the range of 3-8% of total).
This effectively helps to 'pull the tail up' and hence widen the CofG envelope.
HTH
This effectively helps to 'pull the tail up' and hence widen the CofG envelope.
HTH
Joined: Nov 2006
Posts: 1,951
Likes: 90
From: After all, what’s more important than proving to someone on the internet that they’re wrong? - Manson
MD did a similar thing with the 2 smaller NOTAR's, 520 rotates between left and right with the hole in the trash/garbage/rubbish bin going over the top and 600 under the bottom. (From memory) Stand to be corrected on which is which but they differ.
Joined: Jan 2005
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From: Canada
Canted T/R's
If I recall correctly Sikorsky did it first on the S-60 which, in its pre-production variant, had a very aft C of G - so it was introduced to overcome the handling issue. Again, from memory I think it provides about 4% of the total lift on the latest and (allegedly) greatest, S-92.
Joined: Jul 2004
Posts: 376
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From: Durham, NC USA
Just adding the arithmetic for Nick.
The Blackhawk is canted 20º. The vertical component (lift) is equal Tv = T x Cos20º = T x 0.34 while the horizontal component (anti torque) is equal to Th = T x Sin20º = T x. 0.94.
