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EIDW Smith
18th Mar 2011, 16:18
Hey folks,

Basically I did my PPL out in Florida, EFT to be precise. And while i greatly enjoyed it i have just one area i want to ask about before i go out trying to rent a plane here in Ireland.

Because the time frame for a PPL in Florida is often quite short i cant help but feel a bit paranoid that some small areas of nav stuff may have been skipped to stick to the tight schedule. I guess what I'm looking for is an opinion on my own routine.

Finding the distances and headings etc was fine. But when it came to selecting our datum speed (i guess you could call it that or cruise speed?) i just chose the standard 100 kts and then got the ground speed taking into account the wind. Am i missing something? Something to do with altitudes / pressure altitude or something? Or is this acceptable PPL flying?

Just for the record all my navigation so far has been accurate and i don't think it'll kill me any time soon :ok:

24Carrot
18th Mar 2011, 16:39
A good rule of thumb for low levels is 1-6-6, ie:
True Air Speed is 1% higher than IAS for every:
6 deg C over ISA atmosphere and,
6 Flight levels over FL00.

You can also use the whizz wheel.

For low-level bimbles in Ireland, I suspect that errors in the forecast wind will swamp such subtleties.

I would worry more about understanding density altitude!

DeeCee
18th Mar 2011, 16:51
I strongly suggest that you spend some time with an Instructor to make sure you know what you're doing. In any event the club where you rent the aircraft will want to check you out. Anyway, happy flying. DeeCee

kevmusic
18th Mar 2011, 16:54
For Cessna 152 or Robin flying, I've always used 90 kts. What are renting?

Genghis the Engineer
18th Mar 2011, 16:55
Depends what I'm flying, where, and why.

Let's say I was doing a test in a Piper Arrow - it has a really thorough manual, and I want to be withing 30 seconds or so on target. I'll use all the numbers in the manual, and spend considerable time on it.

Let's say I want to fly 200 miles for the day in my own aeroplane. I'll use a standard speed, revise my plan en-route, and not worry about being 5-10 minutes out at the other end.

Where you are on the map is important, being a bit out on times, really isn't - so long as you use instruments or map features to keep the first right, don't worry about being a bit out.

Unless you are taking a test, or flying farepaying passengers with strict timelines.

G