In supersonic F16 lagging?

saberrider · by **saberrider** » 21 Dec 2018, 11:20

In supersonic F16 lagging when pilots pull some G's? I read that will be an normal feature for high speed.

basher54321 · by **basher54321** » 21 Dec 2018, 13:00

Lagging?

Do you mean does an aircraft lose speed when flying over M1.0 and the pilot pulls over a certain number of Gs?

saberrider · by **saberrider** » 21 Dec 2018, 13:07

basher54321 wrote:Lagging?

Do you mean does an aircraft lose speed when flying over M1.0 and the pilot pulls over a certain number of Gs?

No, I mean the jet won't be quick in reaction like in subsonic.

basher54321 · by **basher54321** » 21 Dec 2018, 17:12

Does the Flight Control system intentionally introduce delay into pitch /yaw /roll commands in supersonic flight on top of other existing limits ?

saberrider · by **saberrider** » 27 Dec 2018, 21:59

In general at high speed when pilot increase or decrease G's there is a lag in response. There is the case of the in fighter jet?

johnwill · by **johnwill** » 28 Dec 2018, 00:28

Lags are built into the surface command paths for all surfaces at all speeds and altitudes. The purpose is to make the airplane very responsive without being jerky with overshoot and oscillations. The lags are different at different flight conditions, not just more supersonic lag. Many filters are also in the control paths. The control stick force command to g or roll rate command are non-linear, again to obtain smooth accurate maneuvering, while still maintaining rapid abrupt maneuvers when desired.
This is only a very rough description of how flight controls can be tuned to obtain desired characteristics. The task is enormously complex, difficult, and costly. The people who do it are magicians.

saberrider · by **saberrider** » 28 Dec 2018, 12:33

I read about the formation flying with F16. At lower AoA it is hard to not have overshoot the desired amount of AoA.F18 it is more benign than F16 in this regard. The stick of the Blue Angels is held in place(centred) by spring. The operational F18 don't have to this spring.

saberrider · by **saberrider** » 28 Dec 2018, 17:15

johnwill wrote:The control stick force command to g or roll rate command are non-linear, again to obtain smooth accurate maneuvering, while still maintaining rapid abrupt maneuvers when desired.
This is only a very rough description of how flight controls can be tuned to obtain desired characteristics. The task is enormously complex, difficult, and costly. The people who do it are magicians.

The F16 FBW gains for lower AoA( @degrees) is jerky. Then is smooth enough until 15 AoA then you can overshoot the desired amounts of rates.