Gnav
 

A certain well known pilot shop, well known to have shops at Shoreham and Fairoaks, has for some years sold an 'alternative' system of navigation called GNAV.
I'm interested in giving this a try, however I've never seen anyone using this system, nor have I seen anybody buying it in the pilot shop, nor have I seen any magazine articles about it and instructors I have spoken to seem to know nothing about it. I suppose it must sell because it has been on sale a long time.
Does anybody have any experience of this system that they could share with us?
Best regards,
BroomstickPilot

Re: Gnav
 

BP,

If you mean the Gnav Vortrack system, I use it and think it's brilliant! You simply place a stud through the VOR you want to use, and then clip the arm onto it. Tune in the VOR, ident it, and then pick up the radial plus the DME - turn the arm to radial and then find the distance, and hey presto, a damn accurate position fix. It saves the hassle of having to use two VOR's etc.

My only gripe would be that they don't give you enough of the plastic stuff to do more than 12 VOR's, and if you change your map everytime the CAA updates it, you either end up buying more of these, or carefully removing and reapplying - I've managed this once, not sure if I'll get away with it again!


DW

Re: Gnav
 

dwshimoda, If you go to your local haberdashery you can get press studs much cheaper then stick cellotape over the backs once you have push them through the VOR location then mark the North with a permanent thin tipped felt tip pen.

Re: Gnav
 

Laundryman,

Excellent thinking - I just need to find a haberdashery shop! Thanks for the tip.

DW.

Re: Gnav
 

Your local John Lewis should be able to help.

I tried it once (during TopNav) and didn't get on with it at all!

Andy

What's wrong with a thumb or if you really want to be accurate how about looking out the window and comparing it with the chart. A lot cheaper and more reliable.

If all else fails a GPS with a moving map should do the trick.

The chap who invented it (alas lately deceased) was a prime sponsor of TopNav comp, which became his marketing medium and all long before GPS.
Not easy to use as map folds are always in the wrong place, giving too large a spread on the knee.
Suggest forget it and stick with track-line and watch, basic VFR tools; and GPS as your back-up.

No, buy the best possible moving map GPS and use it as the primary navigation device. Back it up with VOR/DME whenever receivable. Or map reading if there is something to look at.

Anything else is unnecessary hard work - even if the CAA safety evening presenter refers to it as "good airmanship".

IO540,

I thought that was the definition of good airmanship? :}

TPK:ok:

GNAV was invented by Gordon Wansborough-White, who sadly died last year, a thoroughly nice chap if a little obsessive on the subject (Gordon had in an earlier life been an operational Sunderland pilot). His work on the top-nav competition, and with other bodies such as RIN was well known, and admirable.

VORTRAK is a great system, that was pretty much separate to GNAV, and basically uses two clever little pointers to give your position from a pair of VOR beacons. Jolly good idea, and makes a known task much easier.

GNAV was essentially based upon the assumption that you did virtually all of your cruising at about the same TAS (reasonably fair) and so the best way to fly was not to mess about with a whizz-wheel constantly, but to simply carry on your kneeboard a small table of corrections for different conditions flying at that speed. This worked very well.

In my opinion however, where Gordon let himself down was by adding onto this a whole and unnecessary system of navigation which really just became far more complex than the approach he was trying to discount as over-complex. This led to the occasional, and not entirely unjust, accusation that he had a solution looking for a problem.


But yes, I'd say it's worth looking at - ESPECIALLY vortrak, but if you dabble with GNAV I'd strongly recommend looking behind it and cherry-picking the useful bits, don't necessarily adopt it as a whole (or you'll end up as confused as I was!).

G

zzzzzzZZZZZZZZ :D

Thanks to all concerned
 

All good stuff!
Many thanks, Guys.
Broomstick.