Use of secondary flightplan

[rondon9898 84]

Hi chaps,

 

I was just wondering about the use of the secondary flightplan in the 777 and, I imagine, the 747 FMS. Does it have any official use or is the use entirely at the pilot's discretion? I'm really asking because if you are flying a route with no alternative contingencies, i.e. only 1 runway, is it the done thing to copy the primary flight plan anyway, or to simply leave the secondary one blank? If someone could shed a bit of light on realistic use of the sec. flight plan for enhancement of my simming pleasure, I'd be most grateful!

Cheers chaps

[Avantime 81]

See here:

 

http://www.pprune.org/tech-log/476809-rte-2-a.html

[Mike777 163]

Hi chaps,

 

I was just wondering about the use of the secondary flightplan in the 777 and, I imagine, the 747 FMS. Does it have any official use or is the use entirely at the pilot's discretion? I'm really asking because if you are flying a route with no alternative contingencies, i.e. only 1 runway, is it the done thing to copy the primary flight plan anyway, or to simply leave the secondary one blank? If someone could shed a bit of light on realistic use of the sec. flight plan for enhancement of my simming pleasure, I'd be most grateful!

Cheers chaps

Hi, John,

 

Not really an expert, but my understanding is that it is good practice to copy the plan entered into Route 1 into Route 2 before takeoff.  If you need to divert you can plan the diversion in Route 2 while still flying Route 1, then switch.  Also, sometimes I have managed to mess up the original flight plan so much that most of the remaining waypoints would have to be re-entered.  In this situation it's much easier to just switch to Route 2.  BTW, I learned the hard way that it is not realistic to enter a flight plan using the Request function while in flight -- it results in strange RNAV data and shouldn't be allowed at all according to PMDG tech support. 

 

Mike

[rondon9898 84]

Thanks chaps that was most helpful - particularly the EO planning after takeoff - I never thought about that. Mike, when you say planning the diversion, how is that done exactly? I know that sounds like a dumb question but I can't quite get it into my head.

[Mike777 163]

Thanks chaps that was most helpful - particularly the EO planning after takeoff - I never thought about that. Mike, when you say planning the diversion, how is that done exactly? I know that sounds like a dumb question but I can't quite get it into my head.

Hi, John,

 

My FSX computer is in the shop, so I can't give a very detailed answer.  But I think you could use the alternative airport function in the FMC to set up your route in Route 2 to divert while still having Route 1, the original flight plan, active. Or, if this isn't possible, it's still good to have the complete original flight plan available in Route 2 while I am making major modifications to Route 1.  Also, Route 2 can be used to have E-Tops alternate routes available, among the many uses described in the Pprune thread to which Iain posted a link.  But for me the main reason to have Route 1 copied to Route 2, is that occasionally I mess up the original flight plan in mid-flight.

 

Mike