40 knot call

[kiwione]

When I was young and stupid, I would throw Pa28 (Hershey bar wing) and REAL aeroplanes [C180/C188/Pa18 etc] against hillsides. In those days we had a real technical method to determine if we would get airborne by the threshold - if you have'nt got flying speed by THAT thistle expect to fall off the end and gain speed in the valley.
Now I've qualified on above 5700kg and kept my Grade One (notice no mention of stupidity gained or lost) I stand by a 'rule-of-thumb' that if I haven't got 70% of VTOSS/V2 by half-way down the runway then thngs are probably going to get ugly.
I hope this summarises CAO 20.7
Happy flying:ok:

[HI'er]

"by half-way down the runway"...............runway lengths vary from less than 2,000' to in excess of 12,000', with varying types of surfaces - grass (long/short), gravel, sand, sealed - gradients, and elevations.

The 80/100 knot calls made by the "big boys' ", are NOT for the reason you have stated above.
If you REALLY feel the necessity to twiggle the toggle, then a better understanding and use of the P charts applicable to the aircraft type, and take-off airport(s) on your day of operation, will go a long way to making you a safer pilot than your current practice. :ok:
(Don't forget - blue above, green below).

[Ice Vanes]

Wow

sounds like all the components on your >57000 endorsement wern't quite covered.

(But you're probably just a funny guy and just kidding us all, right.......:D )

[Cloud Cutter]

HI'er, I think it's obvious he is talking about short strips, in which case 70% at half way would be a very good, practical performance indicator. When it comes to 30 year old light aircraft, P-charts may not be worth the paper they're printed on - they are deffinately only a guide, there's just too much variation in performance from aircraft to aircraft.

All though I do agree that in anything a bit bigger, performance does need to be calculated more accurately. Please don't automatically knock people for applying a bit of common sense, there are far too many pilots who lack it. There will come a point when you reach the limit of 'the book' and will have to save your own ass.

[Capt. On Heat]

Hi'er........Yep good.

Cloud Cutter....Better!

[kiwione]

Gee, the fishing is really good in this river!!!
BTW, take a look at a certain HS748 operation in an Indian country I've been where overweight aircraft are getting airborne without water help and refer me back to the 'correct technique'.
Before you bite me HI'er, I limited to the WAT tables, cross-checked the ASI's, acknowledged V1 and rotated when my mate called V2/VR
;) ;) ;)

[HI'er]

V2 actually occurs after Vr.
You sound like a little boy who's just discovered his pee pee.
Playing with it in public is only making you look like.........a little boy who's just discovered his pee pee :p

[MOR]

I think he meant V1=Vr... unless of course it is a VERY short strip... in which case they are all different!