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Welcome to the CPL Performance question and answer forum. Please feel free to post your questions but more importantly also suggest answers for your forum colleagues. Bob himself or one of the other tutors will get to your question as soon as we can.
Loved the discussion always good to analyse everything as we are always challenged by CASA and Air Services with trying to present some sort of coherence of the concepts that is supposed to be presented by the legislation
Answer back from the CASA airports engineering guru -
Firstly, the comment in the current MOS 139, para 188.8.131.52 (b) about stopway not being involved is incorrect and has been edited out of the new MOS 139 document which is due to be come into effect next year. The diagram at 184.108.40.206 is correct.
TORA is the length up to the white runway end line that stretches across the runway at the keys. Beyond this point you are expected to be airborne but at least in ground effect accelerating to climb speed.
TODA is the TORA plus all of the available distance to the end of the runway strip by which point you are expected to be at no less than 35 ft.
The stopway is not a mandatory inclusion but if it is provided it needs to be the same surface as the runway proper so that an aborted takeoff will see you hopefully stop on the bitumen.
The clearway is very commonly a grassed area beyond the end of the bitumen and up to the white gable markers. It is not required to have the same strength as the runway and is not required to be 100% level but the land itself must not exceed a 1.25% slope starting at the end of the TORA and climbing away from the runway.
So, the TODA will include stopway and clearway to the white gable markers which mark the boundaries of the runway strip.
The comments revolving around the ICAO difference refers to the Australian practice of allowing the airport operator to declare the grassed area between the runway end and the gable markers as clearway. The last sentence in the paragraph about stopway has been tacked on and is incorrect and does not relate to the ICAO difference.
There you have it.
Engineering specialist in aircraft performance and weight control.
Firstly, the comment in the current MOS 139, para 220.127.116.11 (b) about stopway not being involved is incorrect and has been edited out of the new MOS 139 document which is due to be come into effect next year.
That removes the ambiguity nicely!
The diagram at 18.104.22.168 is correct.
From the diagram at 22.214.171.124 (below) we now have three definitions for TODA in Australia
1) TODA = TORA + EOS (End of Strip)
2) TODA = TORA + Stopway + EOS
3) TODA = TORA + Clearway (The training text book definition)
Obviously 1 & 2 can be combined to TODA = TORA + distance to end of strip (something that you do not see in the training text books)