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Old 25th October 2005 | 03:43
  #20 (permalink)  
Chimbu chuckles

Grandpa Aerotart
 
Joined: Jun 2000
Posts: 4,579
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From: SWP
Ghengis how can one make an informed decision on whether a strip is suitable or not without having a knowledge of the difference between T/O or Landing roll and distance...either available or required?

If you approach to land on a normal 3 degree slope (and single engined light aircraft don't generally but it gives some basis to begin understanding) that equates to 320'/nm. 320' every 6080' or 50' every 1000 odd feet.

Now I think a C152 approaches steeper than that but since it's been 20 + years since I flew them a lot I have no idea of a super accurate figure....to be conservative lets call it half the foregoing...500' before the aiming point you pass 50'...151m. So a minimum of 151m (my first estimate you will recall was 200m which I think is more accurate but still conservative) out of the 370m figure from the first post is before the touchdown point. These rough figures seem to gell with bose x's POH.

The touchdown/aiming point on strips of the type discussed here should be between the first and second cone marker...if not down by the third cone marker good airmanship dictates a go around in my opinion.

The 50' screen hieghts are certification figures...how many airstrips actually have a 50' tree/hill/building/power lines at the bitter end of the TORA? Precious few.

I am all for being conservative with new pilots just starting out but is not 3 times the landing run required being available conservative enough? In my opinion a 30% buffer is completely adequate unless conditions are extreme....far to many pilots buffer their buffers for no good reason and then decide something is not safe, possible or 'legal'.

In PNG for reasons, generally, of DA and slope the vast majority of strips did not fit on the P charts at all and yet we generally took full loads in and out safely and with ease...I am not suggesting bush flying is the realm of newly minted PPLs but some common sense must be taught and applied lest the aircraft's basic utility be ignored and the nanny state/fun police be allowed to take over

Brgds,
Chuck.

editted for poor spooling.

Last edited by Chimbu chuckles; 25th October 2005 at 04:51.
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