Navigation question.....

[beeker46]

I know about flying the Radio Ranges in the mid-40s, the VORs in the 50s, but along come the jets in the Classic Era. In 1959, how did the jets navigate? Same as the DC-6/7s and Connies, by VOR to VOR? As it pertains to FS, that is... I have plenty of routes sketched out using VORs to simulate flying the Civil Airways, covering how the old Radio Range routes were, would that still be viable if flying a DC-8, or 707?

Thanks in advance.

[Tom/CalClassic]

I assume they used the High Altitude Airways, instead of the Low Altitude Airways. Other than that, not much difference inside the US.

Over water, they used the newly developed INS systems a few years after they were placed in service. Before that, LORAN, etc., just like the propliners.

[mdeval]

Included in there somewhere, if memory serves, at the time of the early jets and before INS, is Doppler navigation. Don't understand it enough to even begin to explain it though. At Barnes and Noble the other day, I came across a book on the history of navigation. Looked really fascinating. If it's still there next time I go, I'll most likely buy it. Actually my birthday is this W/E. Hmmm, maybe my wife. Yeah, that's it !


Mike

[dave mcqueen]

For jets in the USA at or above flight level 180 they used Jet airways - ie J84, J110, J80, etc defined by radials of Vortacs; below that they used low altitude airways - ie V6, V23, V25 etc; or they could also use direct routes from one NAVAID (VOR) to another if no airway was defined; and don't forget ATC - if radar service was available ATC could provide a radar vector to a distant location.

Over water Doppler and loran were the primary navigation methods as well as celestial nav, flying a rhumbline and dead reckoning. INS didn't come along until the 1970s and it was not particularly accurate at first - routinely aircraft would pop up from non-radar coverage areas 20 miles or more off course. Later came the Omega navigation system that used VLF networks (in use from 1971 until 1997). Very often when an aircraft was cleared direct somewhere via Omega navigation the aircraft would veer off course 30 degrees or more until the aircraft's equipment locked in the signal. ATC had to be aware of that possibility and provide an initial heading until Omega locked in if there were potential traffic conflicts.

[Defender]

Re Tom's comments, I would just add that if you're using the FS flight planner then make sure you use the "high altitude airways" option and not "VOR to VOR". Because aircraft at high altitude get better reception from the line of sight VOR signals, the high altitude airways followed a more direct routing, so missing out some of the VOR's that lower altitude flights used. 

Bill 

[beeker46]

Thanks all for the input, clears up that question.