View Full Version : JAA/ICAO Defs of T.O. Performance

13th Feb 2008, 04:02
Can someone help me with the following questions? I live in the states and I'm not familiar with the acronyms used.

1. What is the def of TORA?

2. What is the def of TODA?

3. What is the def of ASDA?

4. ASDA is TORA + what?

5. An increase in stopway would increase:


6. A change in clearway would change?


I think ASDA is the same as ASD (accelerate stop distance) in the states...but I'm not sure.

Thanks for your help.

Max Angle
13th Feb 2008, 10:41
It's been discussed a million times on PPRuNE. If you use the search function you will find all you need to know. :)

Pugilistic Animus
13th Feb 2008, 17:54
Why not?---my turn:}

ASDA: distance to accelerate to the decision speed V1 and then stop---unfactored

stopway: a length of usable surface not designated a runway i.e the 'chevron' area that will not cause significant damage to the plane

clearway: an obstacle free area [like water or a field or rusty nails] over which a portion of the OEI acceleration section to the screen/ fence [first segment] to V2 may be allowed

ASDA =accelerate stop distance =TORA + stopway

TORA=Takeoff runway the aircraft must be airborne at V2 [for the accelerate-go] at 35' above the end of the TORA with one engine inoperative: for all engines the FAR TORA includes a safety factor of [half the airborne distance to 35' plus 15%


'sometimes the distance TORA or TODA must be reduced to account for LOW CLOSE IN OBSTACLES affecting the accelerate-go'


1. b
2. c

yes, ASD [FAA] = ASD [CAA]

but in the US TORA=TODA=ASDA
[this is going to change if it already hasn't in the US]

Pugilistic Animus
13th Feb 2008, 21:05
Oh I forgot

the 'A' as in ASDA means available
takeoff runway available TORA
takeoff distance available TODA

and for JAA I believe the all engines factor required is 1/3 the airborne distance plus 17%

15th Feb 2008, 22:47
Thanks for your replies. You guys are a lot easier to talk to than the wanks (whoops, I meant yanks).

Pugilistic Animus
19th Feb 2008, 18:37
Aviationluver thanks for the complement about 'being easy to talk to' but I was born Queens, NY :}