Cosync From Mexico, joined Nov 2001, 556 posts, RR: 0 Posted (11 years 6 months 4 days 4 hours ago) and read 954 times:
i was just wondering are there any autopilot systems that allow u to select a heading and and the plane will fly that heading and automatically point the nose in the right direction to compensate for the winds? i know that u can just keep ur eye on the FMS and adjust the heading bug to make it so that the drift counter goes to 0 degrees. but i was wondering if there are any heading holders that do it for u?
Airplay From , joined Dec 1969, posts, RR: Reply 2, posted (11 years 6 months 4 days 3 hours ago) and read 904 times:
Autopilot "Heading" modes by definition do not apply wind correction. If they did, it would be called "Track" mode.
For the most part, AFCS (automatic flight control System) heading mode is only used to intercept tracks or courses and in the event that ATC issues vectors during the approach phase.
If some aircraft had a "wind corrected" heading mode as you suggest and others had a conventional heading mode, there is increased potential for collision.
For example, if you had 2 aircraft on parallel tracks, one with "wind corrected" heading mode and the other without, and both were issued a heading vector from ATC to maintain 120 degrees, then if the winds were right, one aircraft would eventually drift into the other aircrafts flightpath.
Some FMSs have an "FMS Heading" mode which simply supplies the AFCS with psuedo-heading reference using the selected RNAV mode (INS/LRN/FMS/GPS etc.). The FMS actually takes out any correction for track or winds in this mode. The convenience of this mode is that the pilot does not have to switch AFCS modes to execute vector commands.