Vigilant Pilot:

The Minimum Eye Height over Threshold (MEHT), It is the lowest eye height over the runway threshold at which an on-slope
indication on the PAPIs will be seen for a given approach.:bored:

Reference Datum Height (RDH) is the height that the aircraft should pass over the threshold on a 3 degree approach (normally 50').:zzz:

Professional Stude:

A Daysack is useable at night, however it should be referred to as a Knapsack at sunset until sunrise.:ok:

Co-capt: I could answer your first question but it would see the Geek-Police go into overdrive!!

I'll get my coat...

RDH is used for JAR/OPS landing distance performance calculations.

MEHT allows calculation of landing gear clearance at threshold - only usually important on very large aircraft.

The touchdown zone is the long thin grey bit just after the big green bit with the lights on sticks.

Nothing matters very much, most things don't matter at all.

Hell if you cant touch down in the "Assault Zone" you suck anyway!!! :ok:

Runways? I thought the desired landing spot was usually marked either by:

= a burning LOH (for SASless)

= a bloke with twigs in his hat / Oakley specs (delete as appropriate) holding a dayglo flashcard or an IR strobe.

NOW HERE IS THE CORRECT ANSWER AFTER ALL THE DRIVEL :ok:

Regulation, regulation, regulation......

Both ICAO Annex 14 and CAP 168 require aiming point and touchdown zone markings for certain classifications of runways. It's a certification / licensing requirement.

In the UK, MOD aerodromes are not subject to ICAO/ CAA oversight and hence signals, signs and markings are as per the relevant JSP.

This may change in the future due to European Harmonisation (don't worry chaps you'll hardly feel it) but the EU have yet to decide.

Sur le incontinence, many Mil aerodromes share a civil side so Annex 14 applies.

There is a distance relationship between the ILS GP, PAPI origin and the runway markings, so even though it may work at a subliminal level they all help. Or have not yet been shown to be an hinderance:sad:

Sir George Cayley

Well, thank you, Sir George.

After all the great banter and theories, it's nice to get the answer from the Father of British Aviation. :ok:

I should have written to you in the first place.;)

BP's comment about the positioning of the markings at Brize is very interesting. I wonder what happened there. Perhaps some miscommunication along the lines of how XXIX Squadron ended up with XXX on their aircraft!

I42

The Breweries never made XXIX beer! Simple as that.