Here is my latest article. Hope you’ll give it a look. It’s about three critical tactics anytime you are on the runway. A heavy TOLD (takeoff and landing data) discussion as well.
Thanks!
Good article, Buster.
Regarding the concept of a refusal speed: I always wondered about the idea to take an aircraft into the air with an engine problem on board just because there is insufficient runway to stop. This might make some sense in CAT or military aviation due to the high speed on the ground. But in GA I’d much rather just overrun the runway and smash into some bushes or a fence at the remaining 20 kt than taking my problems into the air and add lots of potential energy to the already lots of kinetic energy that can kill me.
Of course some runways have cliffs or solid barriers behind them, but many don’t. A run way overrun seems to be safer than takeoff to me in most cases.
Good article. It is really a V1 for SEPs.
One thing which works against a late takeoff abort is that so many of them end up in everybody being uninjured and dying in a burning wreckage – because you were travelling at almost flying speed, so the aircraft will comprehensively disintegrate and avgas tends to catch fire easily. It’s a classic in the bizjet world, but in that case it tends to be a runway overrun. And, most GA runways here in Europe are so short that you reach Vr and have to lift off at most a few seconds afterwards.
MedEwok wrote:
Good article, Buster.
Regarding the concept of a refusal speed: I always wondered about the idea to take an aircraft into the air with an engine problem on board just because there is insufficient runway to stop.
It isn’t necessarily an engine problem. Some flashing light, electrical failure, hatch pops open – lots of reasons you might want to abort a takeoff.
For most VFR operations nothing is essential apart from the engine (well loss of a control surface or structural failure would be!). So any problem apart from and engine problem can be taken into the air.
As regards engine problem, in an SEP, I’m with MedEwok. Better to run off the end than take a failing engine into the air.
The other big problem with such V1 speeds as described in the article, is that most GA airports don’t have any distance indicators. So you’re just guessing how far you’ve travelled. So you’re roughly half way down the runway, do you speed check and it’s 90kts instead of 100kts….by was I really 1/2 way or just getting close to it?….opps too late!
I’ve noticed in Germany many have 1/4 1/2 3/4 signs which are useful, but I’ve never seen any indication (or 1000ft boards as mentioned in the article) anywhere near here. So it’s all very fine knowing that I need to see X kts after X meters but if I’ve guessing what 100/200/300 mtrs is, then it’s little use.
The 70% of Take Off speed by 1/2 way is a good judge if I will actually take off, but it’s no real indication on if my engine is performing as normal as different length runways mean that I’ll be at different speeds by 1/2 way.
JasonC wrote:
It isn’t necessarily an engine problem. Some flashing light, electrical failure, hatch pops open – lots of reasons you might want to abort a takeoff.
True. In that case it might obviously better to do a circuit and land again. But one may have awfully little time to decide. I’d think the more serious the problem is the more one should consider staying on the ground even if it means overrunning the runway.
Depends on what is at the end of the runway 
In SEP I generically teach (at application of power for takeoff) check of:
RPM
Ts and Ps normal
Airspeed increasing normally
You can detect an abnormal acceleration quite quickly in a takeoff run and hopefully any TODR shouldn’t be that marginal that anyway if the safety factors are being used.
I think trying to export twin and commercial type performance calculations and the notion of continuing a take off with a failure beyond a certain point in SEP is utter guff to be honest.
As the owner of a fairly unique permit type a/c for which there is no really accurate performance data (TOLD) I am delighted to read this article. It has been on my mind for quite some time to establish actual data for my own aircraft and one of the dilemmas I have is knowing actual distance travelled from brakes off to 50ft since runways have no distance markings. I have considered using a walking/cycling app but naturally the would require the co-operation of another person on board.
Ultimately I would look to compile data into a spread sheet.
Balliol wrote:
I think trying to export twin and commercial type performance calculations and the notion of continuing a take off with a failure beyond a certain point in SEP is utter guff to be honest.
Did you read the article? He doesn’t suggest that at all. So if a hatch popped open or an alternator light came on you will always abort if you are on the ground?
