oly720man From United Kingdom, joined May 2004, 6179 posts, RR: 11 Reply 1, posted (2 years 10 months 22 hours ago) and read 1802 times:
I expect a Hughes insider will be needed for this one. I have no idea of the design/aerodynamic compromises that go into helicopter tail designs
Given that the 500D with the T tail was about 50% heavier than the 500C with a bigger engine and 5 bladed rotor rather than a 4 bladed rotor I imagine that there are quite a few issues that are involved.
The lateral surfaces are, I would assume, of main benefit in the cruise and some dynamic pitch stability in the hover/low speed with the angled surface on the C contributing something to yaw, something that a more effective tail rotor on the -D may compensate for. The position of the top of the T may put it in a cleaner airflow than the lower mounted surface on the -C, but I expect such info is proprietary.
Man City p3 w3 d0 l0 f4 a0 P9 - hey it may never happen again!