Flying question

**metrowestflyer** · 06-01-2012, 01:14 PM

Learning to fly the B707. Using the AP. When I lower the flaps it tends to gain altitude really fast and drops when flaps raised. How do you stop this action. (other then not use the AP?)

**jgf** · 06-01-2012, 08:02 PM

Lowering the flaps increases lift and it takes the AP a while to register and compensate; this is normal and should be taken into account when deciding when and how much to lower the flaps.

That said, you can possibly make the AP respond faster by tweaking the pitot_static section of the aircraft.cfg:

vertical_speed_time_constant=1.0

"The vertical_speed_time_constant parameter can be used to tune the lag of the Vertical Speed Indicator for the aircraft:
- Increasing the time constant decreases the lag, making the gauge react more quickly.
- Decreasing the time constant increases the lag, making the gauge react more slowly.
- A value of 0 effectively causes the indication to freeze. If an instantaneous indication is desired, use an excessively large value, such as 99.
- If the line is omitted, the default value is 2.0."

If the section isn't in your aircraft.cfg, add it (with pitot_static in brackets as other sections). Looking at several commercial airliners in my hangar there are values from 5 to 98.

**freakbear** · 06-01-2012, 08:04 PM

Hi, is this the Captain Sim model? I remember vaguely more people complained about the autopilot. I even believe there was an update for this. Although I have the latest model the sudden drop problem sometimes returns. The CS C-130 also has some strangeness in it's autopilot. I came to the conclusion the default MS AP works best. Although the models are reasonably flyable I can't use them in FSPassengers because the passengers complain immediately after a short drop.

For the 707 I advise you to gain altitude by hand first and then simply lock the aircraft at that flightlevel with the AP. Also don't hold the AP up/down "stick" but click it once or twice to go up or down.