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I would think that having a huge mass spinning around should produce massive gyroscopic forces when turning or pitching.
There must be some clever way of minimising or eliminating the effects... How is it done?
(An example of the sort of thing I am talking about)
The AWACS surveillance radar components consist of multiple units grouped in 3 locations. Only the antenna array and its electronics are in the rotodome.
The receivers, radar processors, and radar control & maintenance panel are in the main cabin.
While fiberglass and rubber make up the outside coating of the dome the inside is mostly hollow except for the antenna rays.
AWACS aircraft produce greater drag relative to that of civilian jet liners. Therefore, engines for AWACS require non recurring engineering(NRE) to handle the dual generator requirements of the aircraft.
In order to reduce its air drag during take-offs, and while flying endurance speed the dome is tilted down 6° at the front. The rotodome itself is hydraulically rotated. Remember, the Boeing 707/320 from which the Boeing E-3 Sentry was derived can very easily carry a huge cargo load . Therefore, the addition of a 1.5- 2 ton rotodome makes no difference to an AWAC which in any case is not carrying more than 20 – 30 crew members.
Generally the radome scans at 6 revolutions a minute. When the radar is not operating the radome rotation rate is set at 1 revolution every four minutes ( In case of the E-3 it is 1 rotation every 10 seconds). Ergo, the torque that the rotodome produce is very low.
On the E2 Hawkeye the dish does not rotate very fast (ie, very slowly), and so the torque is probably negligible. Usually the radomes are designed to help generate lift, and while certainly not as effective as a wing, do offset their own weight quite a bit.
