Calculation of runways

[TFC1]

I have a question regarding the calculation of runway lengths, does the sim use the general runway strip dimensions, or TODA (Take-Off Distance Available), TORA (Take-Off Run Available) or LDA (Landing Distance Available) for calculations? From my knowledge of Norwegian airports, one can encounter highly differing numbers within those values. 

[Sami]

No, it's one figure for all.

[TFC1]

Ok, do you use the physical length of the runway, or which figure is valid?

[Sami]

In most cases LDA/TODA etc are the same, and I suppose the figures are the actual lengths of the runways. So a stopway isn't there but a displaced threshold could be. Not sure actually, have never compared any such airport against AWS data.

[TFC1]

I had a look at the data for ENCN, and while the physical length of the runway is 2030m (as stated in the airport data), the maximum TODA is 2120m for rwy 04, and 2060m for rwy 22. Or, if you use the TORA, the numbers are 1970m for rwy 04 and 1910m for rwy 22. Now as I see it, that could have an impact on what size of aircraft I could operate from ENCN, or even what payload I could fly out with. (The LDA is even shorter, 1910m for rwy 04 and 1860m for rwy 22, but that means less than the take-off run available.)

As an example, Spanair used to operate charterflights with MD83s from ENCN to GCLP via LEST, the reason for the tech stop being that the departure runway was too short. But in the sim there is no problem flying a fully loaded MD83 (with HD seats) from ENCN to GCLP in one hop.

This may be nitpicking, and it may not even be possible to verify for most airports listed in the game. But as you can see, the runway available may be somewhat more or less than the stated dimensions of the runway. I don't know how accurate this should be, but I'm sure we could organize a data collection from various airports around the world with the longest TORA or TODA.

(I'm an air traffic controller, so that could probably explain all this... )

[Sami]

I guess in that example it would be wiser to change the length to TORA?

However I don't see it necessary to check these globally, only some already known airports could be updated.

[TFC1]

Yes, the TORA would be the correct value in this example.

I agree with you on not having to check all airports, I'm quite sure that most airports with runways of more than 2700m are fine.

What kind of format would you need the information in? I'd be happy to go through some of the Norwegian airports to see if there are any major differences between the physical length and the TORA.

[Sami]

excel file for example where column 1 is airport icao code, 2 is the full rwy length and col.3 is TORA?  if 'human readable' remarks are needed put them to column 4 (or D in excel language).

One airport per line of course.

[TFC1]

I'll have a look and let you know 

[TFC1]

I've had a look at the Norwegian AIP, and checked some of the larger airports. Judging by the difference in runway length and the TORA, there might be a few incorrect airports aroud the world. I'd assume that one should look at the shortest TORA to get the correct value, as this would reflect more on real-life ops. One doesn't always get the longest runway for take-off  .

And I checked EGLC/LCY. While the runway there is 1508x30, the TORA in both directions in only 1199m. Kiss your 757 ops goodbye, folks  

[TFC1]

Update on this - I apologize for taking a loooong time to get through this, but I'm making progress. I've made an excel-file with data for Norwegian, Swedish, Danish and UK airports with differences between physical runway length and TORA (actually discovering that a few airports have longer take-off runs available than the published length of the runway  ). I'm hoping to do France and the Netherlands tomorrow, and will see if I can do more pretty soon.