departure procedures-obstacles?

[stator vane]

whilst studying for the ATP air law and using Bristol's, Oxford's and Pooleys, i still have a question if there is anyone out there that can help.

first, Oxford's 7.3.1.2-
blah blah blah, then "the minimum obstacle clearance equals zero at the departure end of the runway (DER) and thereafter increases by 0.8% of the horizontal distance in the direction of flight, assuming maximum divergence of 15 degrees"

then as we turn the page, we see a diagram titled "Procedure design gradient"

my tired eyes noticed that above the DER, there is a 5m (16ft) indicated which appears to be the start of the 2.5% gradient.

their text mentions NOTHING about this 5m (16ft) space at the DER.

i reach over and get Pooleys and it appears that he used a Xerox machine and shrunk it a bit and put it in his book. still no explanation as to the source of this 5m (16ft) space at the DER.

Bristol's doesn't even go there!!!

now i realize this is a small bit of nit-picking, but really it is on the same level as to whether embarkation cards can be written in ink or pencil and in block letters that can cause me again to fail the ATP by ONE QUESTION!!!!!

and lest i start off on the insanity of the entire testing system as it seems to be in the UK as well as all of Europe from what the first officers i fly with tell me,

my question is, does anyone know where the 5m (16 ft) come from?

also the Oxford diagram mentions (see 2.2.3) which i cannot find in the Oxford book for the life of me!!!

cheers;

[Empty Cruise]

Hi Stator,

Well, you ripped up an old wound of any IR FI

I have looked everywhere, sent letters to the CAA procedure office & asked all the gurus I've met - an have come nowhere near an answer. My best advice would be to use this approach:

1) Keep asking - and if you find out, please let us (me!) know
2) It's in a drawing - not the text. On that reason alone, I think you would stand a good chance of having a question disregarded or overturned. Your instructor and CGI would probably not have too much trouble getting you of that "hook".

All the best of luck with the exams!

Brgds,
Empty CRS

[mutt]

I havent seen the notes that you are talking about, but it is possible that the picture depicts the obstacle clearance plain from a contaminated runway which has the screen height reduced from 50ft to 15 ft.......

Good Luck with the exams.

Mutt.

[OzExpat]

stator vane... It comes from ICAO Doc 8168 - Pans Ops. You will find out all about it if you read up on the design of Departure procedures (ie SIDs).