Date: 04/29/11 [[BR]]
Location: Tri Valley[[BR]]
Aircraft: Thor[[BR]]
Pilot:  Garrison Hoe [[BR]]
Flights: 5 Thor[[BR]]

**Weather**[[BR]]
Weather was decent; sunny, moderate southerly winds winds with gusts, temps around 50F. [[BR]]
METAR KLVN 291412Z AUTO 18009KT 10SM CLR 09/02 A2991 RMK AO2=

[source:/trunk/FlightData/Control_Laws Link to Flight Data]

We took Thor to Tri Valley today to fly the revised UAV class controllers. Wind gusts made landing challenging, in addition to southerly winds reducing the runway length. We placed the onboard video out on the wing to avoid propeller aliasing. Note that the camera was upside down; if you use VLC player, you can rotate the video.

Note: there was significantly more turbulence than last week, so the data will appear much nosier.

The objectives for the deployment were:

1. Fly UAV class controllers (3), the baseline controller, and two revised controllers to investigate a pitch oscillation noted in last weeks data.
2. Check revised alpha/beta algorithms by doing manual pitch/yaw doublets.

We completed 5 flights with data. The first flight with the baseline controller did not get data due to the tftp server accidentally being closed on the ground station laptop. All student controllers had the same structure as the baseline controller, but with different gains. All programs shared the same command sequence as follows:

1. Level flight for 3 seconds 
2. 20 deg roll doublet, 6 seconds
3. Level flight for 2 seconds
4. 5 deg pitch doublet, 6 seconds
5. Level flight

Controllers were engaged five times on each flight. 

Thor Flight 05: Group 1 controller. New pitch & roll controller gains.

Thor Flight 06: Group 2 controller. New roll controller gains.

Thor Flight 07: Group 3 controller. New pitch controller gains.

Thor Flight 08: Baseline pitch, Group 3 roll controller, for investigating pitch oscillation.

Thor Flight 08: Group 2 pitch (from 4/21/11), Group 3 roll controller, for investigating pitch oscillation. On this flight we did some manual elevator and rudder doublets starting at t = 338 seconds. We also did sustained sideslip at t = 410 seconds.

Issues:
1. On the first flight with the Baseline controller, we left the pitot tube cap on for the pressure zero; however, this pressurizes the static port, so the altitude bias was in error. A better practice is to simply place the aircraft out of the wind for the pressure zero.
2. Observed significant GPS checksum errors during Thor Flight 07. This ticket (#22) needs a fresh look.

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