Auto Pilot Question Please

[CAT3C AUTOLAND]

Hi Captains and Co-Pilots,. .. .Quick question about autopilots please. I am only a PPL ‘wannabee’ airline pilot so please excuse the lack of knowledge.. .. .I have been watching a lot of flight deck videos recently (Intelligent Television and Video series) which I really enjoy, as it is the next best thing to a jump seat ride!. .. .Anyway, I have noticed a lot of reference to V Nav and L Nav. I understand that this function is coupled with the autopilot and controls vertical navigation (altitude) and lateral navigation (heading). However, what controls the V Nav and L Nav parameters? Am I correct in thinking that these are governed by the FMC, and when the flying pilot calls for L Nav, or V Nav the autopilot automatically flies the route dictated in the FMC, whether it be a SID, en route change or STAR? If this is the case, when the flying pilots utilises the heading select function, or the altitude hold, is this for when the aircraft deviates from the planned route in the FMC, for example on a vectored ILS approach?. .. .I would appreciate it if someone could comment of the above <img border="0" title="" alt="[Big Grin]" src="biggrin.gif" /> . .. .Thank you. .. .CAT3C AUTOLAND.. .. .PS. I cannot wait until I can push the V Nav and L Nav buttons myself <img border="0" title="" alt="[Smile]" src="smile.gif" />. . . . <small>[ 19 March 2002, 19:43: Message edited by: CAT3C AUTOLAND ]</small>

[easondown]

Cat3c,. .. .The captions such as ALT, VS, FLCH, HDG when selected and seen on the pfd allow the handling pilot to control the autopilot as it were. ie when being vectored on to ILS etc. .When LNAV and VNAV are seen on the pfd (primary flight display) the input is coming from the FMS ie climb speed, angle of descent and as you said, when on a sid etc.

[CAT3C AUTOLAND]

Cheers onemorehold, appreciate it.. .. .Any chance of a jumpseat ride? <img border="0" title="" alt="[Big Grin]" src="biggrin.gif" />. . . . <small>[ 20 March 2002, 12:04: Message edited by: CAT3C AUTOLAND ]</small>

[easondown]

cat3c,. .. .If it were up to me - no problem, but you know the rules these days !!!. .. .Good luck with the rest of your training

[shon7]

Building on the previous question, say i entered a specific route in the FMC and that route is changed and I am vectored to an intersection and then given instruction to "proceed as filed.". .At this point I switch on the AP. How does the autopilot determine that this is the location where I want it to take over. Do I have to enter this again in the FMC or can it automatically fix its position and resume navigation.

[easondown]

shon7,. .. .If the aircraft is flying the flight profile which has been entered in the fms/fmc it is very easy to deviate from it if required to do so by air traffic. eg if the aircraft is happily flying the flight plan and heading to a waypoint and atc ask you to turn to a heading say 140 degrees then turn the heading bug to 140 and select hdg on the console and the aircraft will happily ignore the fms/fmc and fly the heading. Then if atc come back and ask you to resume your own navigation to a specfic waypoint, just enter the waypoint into the fms/fmc, select direct and Nav, now the aircraft ignores the HDG mode and flies the fms/fmc profile and when it reaches the waypoint it will automatically fly the remainder of the flight plan unless otherwise instructed !!!. .. .Hope this makes sense.

[CAT3C AUTOLAND]

Onemore hold, no problem, just joking.. .. .Out of interest have the CAA enforced new legislation about flight deck visits since Sept 11th?. .. .Again, thanks for responding to my post, this makes interesting reading for us Wannabees <img border="0" title="" alt="[Smile]" src="smile.gif" /> .

[paulo]

cat3c - Sounds like you'd enjoy MS Flightsim. No FMC, but the AP / Autothrottle / Flight Director are there. Great entertainment for a PPL I say.

[easondown]

cat3c,. .. .Afraid so, the b'laden family can no longer visit us!!!!

[CAT3C AUTOLAND]

Dam, Good thing for safety, bad thing for interested parties!!

[???pax]

CAT3C If you get MS Flight Sim be sure to buy the 767 Pilot in Command add-on for it. It has an FMC and there are plenty of downloadable STARS, SIDS, and other routes out there.

[CAT3C AUTOLAND]

Thanks for the input guys, I do have MS Flight Sim, and will certainly look at getting the B767 and on, thanks.