Request T/O Perf Calc for B727-200

[noflynomore]

Following the recent accident to the Aerosucre B727 I'm interested to get a ball-park picture on the differences between various take off performance figures for the approximate conditions that pertained. It would be useful to see a comparison between the figures requested to gain insight into potential motives/advantages for operating at overweight figures as I think few of us have any idea of the differences such calculations might make to a payload.

Rwy length 1800m. Elevation 50m, temp 31'c. wind - let's call it calm. pressure - dunno - call it standard atmosphere.

Three main questions please; generic B 727-200 figures will do, this doesn't need to be super-accurate, it's a ball-park view I'm after.

1) What MTOW is expected for commercial ops under these conditions. (ie V1stop) - sorry, I'm UK CAA - don't know the FAR designation.

2) What MTOW could be achieved by using 1600m as t/o roll alone and disregarding any stop distance? (as the fence was at c. 1900m one might assume they'd think 1600m a "sensible" figure for ground roll) 3) How would these figures be affected by a 5 Kt tailwind?

Any further observations by B727 planning experts?

Mods,
You can see where this request is coming from. I suspect it will gain better response here than in the main thread. Can it please run long enough to get some good "Tech Log" responses before it is combined/binned?

[MarkerInbound]

Round numbers, -15 engines, flaps 15 (I can't find a flaps 25 chart), no runway slope, packs off, your conditions, I get about 155,000 for brake release. We call it the Field Length Limit. Don't know if the limit is accelerate-stop, accelerate-go or all engine 115%

I don't have any takeoff run numbers to answer your second question.

A 5 knot tailwind brings the weight down to 145,000.

[noflynomore]

Thanks MI.

Its the comparison between the Field Length Limit and using the whole runway length as a take of run that I am trying to find, I'm sure you can see why.

Anyone else out there who can find a MTOW for a 1600m ground roll?

[westhawk]

We're a bit short of having enough of the required data to make a proper analysis.

However if anyone really wants to work through the process, here is a LINK (https://www.ssl-url.net/gf3.myriapyle.net/aero/Fichiers/727perfo.pdf?PHPSESSID=446547a6bcecff57db5abf85ac3cd3ba) to a 727-200 performance manual excerpt intended only for training purposes. Unfortunately, this manual excerpt only contains runway and 2nd segment climb limits data applicable to flaps 15.

If the actual flap setting used during the accident takeoff is ever confirmed to be 15, the figures derived from this manual may be of some interest. If the actual takeoff weight of the accident airplane is ever made available, then the figures derived from this manual may be of some use for comparison purposes. I say may because we also don't know anything about the rating or health of the engines, or how much thrust they were actually producing at takeoff. Or how accurate their load sheet was, whether some brakes were dragging, etc...etc...

It's obvious that there is some weight at which the airplane can be taken off from that runway while in compliance with it's limitations under the prevailing conditions of the day. Once the rest of the missing variables affecting actual takeoff performance on the day are accounted for, the proverbial smoking gun just may become visible. Or not.