The XML gauge parameter AUTOPILOT ALTITUDE LOCK appears to engage the altitude select mode.Which Parameter engages the Altitude Hold so that the autopilot will remain at the altitude the aircraft was at when the Altitude Hold button is pressed?AUTOPILOT ALTITUDE HOLD did not semm to work.Some sample code would be appreciated.

>The XML gauge parameter AUTOPILOT ALTITUDE LOCK appears to>engage the altitude select mode.>Which Parameter engages the Altitude Hold so that the>autopilot will remain at the altitude the aircraft was at when>the Altitude Hold button is pressed?>AUTOPILOT ALTITUDE HOLD did not semm to work.>>Some sample code would be appreciated.I am not sure I understand your question, but this is what I use in my AP hold switch(A:Autopilot altitude lock, bool)I believe the the default behavior when the AP master is turned on is to keep the same altitude and course the plane was on. Only after selecting alt hold will it climb or descend to the selected altitude. CheersShad

That is the code I currently have, and it causes the aircraft to change altitude at the default vertical speed to a selected altitude.Many GA aircraft don't have an altitude selector - just altitude hold, they sense the altitude your at when you press the ALT Hold Button, then hold that altitude, simple as that.

try this, Parameter is AUTOPILOT ALTITUDE LOCK VARclick is AP_ALT_HOLDim going from memory so... i 'think' the AP_PANEL_ALT... is the cause of the problem.

>That is the code I currently have, and it causes the aircraft>to change altitude at the default vertical speed to a selected>altitude.>>Many GA aircraft don't have an altitude selector - just>altitude hold, they sense the altitude your at when you press>the ALT Hold Button, then hold that altitude, simple as that.>>>Hmm, you know, that was something I failed to test, but you are right, my ac exibits the same behavior. I also realize that my VS hold is acting the same as my alt hold... not the desired behavior at all.Grrrrr....Shad

Here is what I use in my KFC150 autopilot. When you click on ALT hold button, it nears the current altitude to closest 100, inserts it into altitude hold altitude, and activates altitude hold. If it was previously on, it syncs flight director pitch. Not sure if you need this for yours though. The KFC needs other special approaches to get the "correct" locks too. Only from how I'm able to understand it's manual, I've never flyed with one.Code manually written due to it being on another machine, so bugs and typos might be present: (A:Autopilot altitude lock,bool) ! if{ (A:Indicated Altitude,feet) 100 / near 100 * (>K:AP_PANEL_ALTITUDE_HOLD) } els{ 1 (>K:SYNC_FLIGHT_DIRECTOR_PITCH) }

I use (>K:AP_ALT_HOLD) to keep the current altitude.This is the Alt Hold Mode on the MCP.And (>K:AP_PANEL_ALTITUDE_HOLD) when pressing VS Mode on the MCP.In the aircraft.cfg default vertical speed = 0.So after pressing VS Mode you now can dial the desired vertical speed, after which the plane climbs to and holds the preset altitude.Jan"Beatus Ille Procul Negotiis"

>I use (>K:AP_ALT_HOLD) to keep the current altitude.>This is the Alt Hold Mode on the MCP.>And (>K:AP_PANEL_ALTITUDE_HOLD) when pressing VS Mode on the>MCP.>In the aircraft.cfg default vertical speed = 0.>So after pressing VS Mode you now can dial the desired>vertical speed, after which the plane climbs to and holds the>preset altitude.>>Jan>>"Beatus Ille Procul Negotiis"Question: Why do you need to put the ">" sign in front of the K in the string? For instance, (A:Autopilot altitude lock, bool) is valid. Is (K:Autopilot altitude lock, bool) also valid? What does the > sign modify with regards to the K? Maybe I should read the FAQ again heheh. CheersShad

(>K:...) means a command.Jan"Beatus Ille Procul Negotiis"