My opinion:
Yes, Overhead to Overhead is the shortest route, but I have to agree with the points raised that if you are actually inbound to an aerodrome and an overhead join isnt either available or issued, then what? In the practical world I would beleive a lot of pilot's stop flying their nav route accurately when they either get visual with the field or have received the joining info,I'm talking VFR here. I don't know a lot about it but as someone said when you start doing IFR stuff SIDs start to come into play.
Everyone seems to be clear about reasons why Overhead to Overhead is or isn't practical, but something that I dont think has been mentioned yet is the actual performance issue. The approach I take now to planning routes is I start the route from either a VRP or a prominent feature, (as FNG, tacpot and whirly suggested), this enables yourself to get sorted and start the leg immediately.
The reason I take this approach is because I find it easier, I have time to get everything sorted and once I'm over the VRP all I have to do is "hack" the watch. Another reason (probably because I'm lucky to have VRPs within 3 miles North East and West of my field) is that by the time I have climbed to the overhead I could have got to my VRP, which is also a little more en route.
That's just my opinion, I prefer the VRP approach, as does my instructor, I was taught both, but decided against the overhead route. I won't bother restating the issues already raised about the approximation involved with flying routes such as compass markings and drift, but I do think they are apparent, however, adequate post PPL experience is needed before you can accruately approximate I think, so best stick to your plan and definate drift corrections.
With regards to the test, I would do what you have been taught, this will probably be what you are most comfortable with, be as precise as possible, there are limits on the test, I think its + or - 100 feet on altitude holds, + or - 10 knots on speed, and 2 mins on time, but I'm not deffinate on that. I tried to be as precise as possible, 37 mins was the calculated leg time on my test, 37 mins 13 seconds I think was the actual leg time, it works!
Of course this is totally relative, sometimes overhead to overhead may be appropriate, I woul'd be reluctant to say "i'm only going to fly this type of nav", it restricts your options.
One final point, as tacpot suggests, I'm very wary where and when I do my drift corrections, unless you have the post PPL experince to approximate accurately, which I yet don't , I would stick to correcting for apparent drift at quater or half way points, this is again my prefered method, simply because its nicely spaced intervals, that are easy to calculate using the drift angle, closing angle method, but hey, ways of correcting drift is another thread totally!
Gawd that was a long one! hope it makes sense and helps.
Rusty.
P.S as Cat river says, Height = Sight, and yes I know spelling is awfull, but I'm tired ;-)
[ 23 February 2002: Message edited by: Rusty Cessna ]</p>