Flight Planning Question

[av8trflying]

Hey guys, just a quick flight planning question for your expertise.

If I am flying to a strip that does not have a TAF, (ie country strip in the middle of nowhere) where do you get your temp and QNH from to work out landing and take off charts from?

Cheers

[Arm out the window]

You could use DA from the declared conditions charts - CAO 20.7.0, and look at 20.7.4 for what you're supposed to be allowing for.

Realistically, I'd try to get some idea of what the real temperature and atmospheric pressure's going to be like on the day from the ARFOR and any local met info you can get, work out predicted and worst case scenarios from the charts to see if your proposed operation is feasible in the first place.

Depending what you're flying and what load you're carrying, takeoff's likely to be the most critical strip-length wise, so you could check the temperature and read off the QNH by setting airfield elevation on the altimeter when you're there and confirm the figures you've previously worked out, or crunch it again on the spot if it's tight.

That's what I'd do anyway, others may have suggestions.

[HappyBandit]

Heard of an Area Forecast?

Hey Mate

Area forecasts are good for these type of things! Area forecast covers approx 100 square nm.

[av8trflying]

Thanks for the quick reply. That is what I sort of had in mind.

Would you use a TAF from an aerodrome that is say 50nm away but at the same height?

Happybandit, yes I have heard of these things called ARFOR's. The reason why I ask is because in a test situation I used the ARFOR and got berated for it.

That is why I wanted to see what people in the field use. After all you guys are the ones that do it day in day out.\

cheers

[Captahab]

Not sure why someone would want to berate you for using an Arfor, even IFR (by day) you dont need a TAF if you are going to an aerodrome that does'nt have an instrument approach, provided the arfor is valid and you carry the required fuel depending on the wx.

Ahab

[MACH082]

Use worst case scenarios, so at 40 degress, 2000 ft pressure height with a 10kt downwind the aeroplane will take off and land in XXXm feet etc. If the conditions are better than that, you are covered. I have never met an ATO that would tell you this was wrong.

For my CPL i used this for my Navs and test. I would only get the p charts out if i was on a very short srip and wanted to cover my behind on the actual conditions of the day.

[westernman]

gould what a tool

I hate adrian

[VH-FTS]

Unless you have the actual temp & QNH, as mentioned above you need to use the declared density height charts.

My understanding of the regs is it's not legal if you use a QNH & temp from an aerodrome 50nm away.

As Mach and Arm said, you should have an understanding of your most limiting points. If conditions are 'better' than these, there should be no problem.

[av8trflying]

Thanks guys, that pretty much answers my question.