Rejecting a takeoff

[D 7]

As per our sop, below 80kts we are to reject for a system failure (and then a list of other abnormalities like vibration, slow acceleration etc etc)

So does that mean we reject for ANY system failure. So below 80kts if you see the master caution light come on, do you automatically stop-without identifying why the light came on or finding out the problem?

What do you guys think? What sort of thoughts/mindsets do you keep when on the takeoff roll with regards to rejecting? (apart from hoping you don't have to!)

[Mungo Man]

apart from hoping you don't have to

My mindset is I'm going to abort unless nothing happens, rather than hoping nothing goes wrong.

[None]

high-speed/low-speed RTO

Many companies prefer to comply with the Aircraft Manufacturer's recommendation concerning RTOs. The builder of the jet I fly determined that 80 knots is an important boundary during takeoff...a boundary between the lower speed RTO and the high speed RTO.

The RTO autobrakes in the jet will not engage at speeds below this 80 knot decision point, so the abort will not be as dramatic as with a high speed RTO. Above 80 knots certain events will not illuminate the Master Caution light during the takeoff roll...they don't want to highlight the event until the jet is airborne.

I am on-board with this line of thinking from the manufacturer...both becuase it makes sense to me, and because our leadership says this is our SOP. I have not yet met another pilot at my company who disagrees with this SOP.

Prior to 80 knots abort for:
Activation of the Master Caution
System Failures
Unusual noise or vibration
Tire Failure
Abnormally slow acceleration
Unsafe takeoff configuration warning

Prior to V1
Engine failure
Fire or fire warning
Predictive Windshear Caution or Warning

Above V1:
If the airplane is unsafe or unable to fly

[SNS3Guppy]

Below 80 knots we'll consider anything for a reject. That doesn't mean we'll be rejecting for anything. Above 80 and between 80 and V1, our operator defines any rejected takeoff as a high speed rejected takeoff. In this environment, we're only going to consider stopping for an engine fire, failure, loss of directional control, outward opening door, or condition that makes the aircraft unsafe to take airborne. Beyond V1 we're going flying.

There's noting on our forward caution panel worthy of a high speed rejected takeoff (B747 Classic).

[BelArgUSA]

To RTO, or not RTO, is the question...

Nothing wrong with your numbers and procedures mentioned above.
If "out-of-the-box" numbers, they apply much to the A-320/B-737 types.
That 80 knots if a fine figure to consider.
Operating from a typical 6 or 7,000 feet long runway.
xxx
Consider other (higher numbers) if larger airplanes and longer runways.
No too excessive numbers, just slightly higher numbers.
Certainly, RTO at 100 knots can be considered for a 737 on a 12,000 runway.
xxx
Personally, the earliest "GO" speed in the 747-200 was 120/130 knots.
That is except engine failure or fire/fire warning cases.
But for a 747, you often deal with V1 much higher than 80 knots.
I mention the 120/130 knots to be above VmcG.
A typical V1 for a classic 747 is some 145-160 knots.
This on runways anywhere between 10 and 14,000 feet long.
xxx
Then think about actual conditions, dry or slippery runways.
But again, I would recommend to input the VmcG in you decisions.
Hope we do not get into the old "Pprune V1 discussion" again...
xxx

Happy contrails

[Ty3]

Reject

Many new large aircraft lock out the master warning and engine fire alert at 100kts...only an actual engine failure is recommended for a rejected take-off between 100kts and V1.

[411A]

Many new large aircraft lock out the master warning and engine fire alert at 100kts...only an actual engine failure is recommended for a rejected take-off between 100kts and V1.

A very wise decision.

[Port Strobe]

But for a 747, you often deal with V1 much higher than 80 knots

BelArgUSA, not sure if you've flown 737 but on -700 at least then 105KIAS is a decent catch all figure for Vmcg for minimum go speed.

Many new large aircraft lock out the master warning and engine fire alert at 100kts

Ty3, would you be able to quote any of the types that do so please? I'm aware on certain types inhibitions are in place in the high speed regime regarding cautions, then warnings after V1 until at 400' aal but I haven't heard of fire warnings being inhibited between 80/100 knots and V1, one could interpret that as being rather too "go minded" from the outset. Given a long enough runway then stopping for a fire warning right up to V1 when not field length limited is arguably safer than continuing, especially if it's a cargo hold fire say with only one extinguisher bottle. That is entirely dependent on the type and scenario I understand but just an example off the top of my head.