jjleo

I'm a rookie here, I have a question about the FMC nav point.

If there is a SID for a airport which which it's not avilable in the FMC, and the first point is at the runway heading and when you climb to 3000'. Then how can I make this point in the legs?

And if you can give me some more tips about the FMC, I will be very appreciated!

Rainboe

It would be acceptable to make a fix of the Airport code, or even the geographic reference point of the airport. Then use that fix to create a new fix of: Airport then Runway Heading/10 miles, like ADCD235/10.

It is accurate enough without other navigation aids.

Then get the other pilot to check it independently.

IRRenewal

You cannot create conditional way points (ie turn at 3000').

Using 10 miles is a poor and highly inaccurate substitute.

Raw data is the only answer.

flite idol

Thats correct, a pilot cannot make a conditional waypoint enrty, it must be database generated. Confusion often arises with the terminology, pilots can enter a constrained waypoint but not a conditional waypoint.

Rainboe

Yes, very good. The 10 mile point was just chosen arbitrarily as a point to aim for. Then, when you get to 3000', you then do whatever comes next in the SID. I was not suggesting 10 miles as anything but a point at a suitable distance to steer for giving you a track while you wait to get to 3000'! You cannot spend 20 minutes constructing your own SID- better to give a point to go for and then.....follow the instructions!

411A

Really?
Gosh, that particular FMS (LNAV) is far behind what the FMS in the 'ole L1011 could do...over thirty years ago.

Back to the future...

Jesper

Are you sure you're in the correct forum? Ms Flightsim is discussed elsewhere.


You can create temp waypoints in the nav database. Just input a name not currently used on the nav ref page and then specify either coordinates or bearing/range from a stored waypoint.
All waypoints have coordinates in fine text published on the Jeppesen plates.
The easiest way is to insert waypoints directly in the legs pages using range/bearing from stored waypoints to build your routes.
Check chapter 11 in FCOM2 for more info.

BOAC

- spot on, Jesper! I cannot believe this is being answered here like this in a professional pilots' forum.

jj - you cannot LEGALLY fly that procedure in LNAV which is what I suspect you wish to do. You would FAIL an IRT if you tried that, apart from possibly having an airmiss with other traffic. With any wind other than directly up or down the runway you would NOT maintain 'Runway Heading' in LNAV which is your clearance. IGNORE the advice you have been given here. 'Runway Heading' does not go to a fixed point. You cannot fly 'Runway Heading' in LNAV UNLESS you use 'Intercept the leg to', but as IRRenewal has correctly pointed out that will not work for a conditional waypoint in a 737. You CAN of course fly 'Runway Track' in LNAV if you need to.

There is a knob on the control panel labelled 'HDG'. Set 'Runway Heading' there and fly that until you see the numbers '3000' on your altimeter. Then do what comes next. If that fails, ask a 737 training Captain.

jjleo

Thank you all for your advice and help!

So there is no such a way to make a conditional way points in the FMC. If the SID is like that i can use the HDG sel first until I got the next leg in the flight. Then use LNAV.

Thanks again, and I like the professional here. Though English is not my native language， I can still got a lot of help here. But sometimes maybe it will get you some trouble to understand what I'm saying!

Rainboe

Help is welcome, your English is just fine! Any problems, just ask.