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layman
16th Aug 2021, 21:55
Searched but couldn’t find a thread on this.

Brisbane VH-VFF 23 October 2020

25 mm screwdriver bit damages engine after being there for around 100 flights

ATSB report
https://www.atsb.gov.au/publications/investigation_reports/2020/aair/ao-2020-058/

No injuries. ‘Only’ damage to an engine.

Thought it interesting the pilots mentioned the ‘startle’ factor - real world being both louder and with more vibration, than a sim. Also they had never practiced a low-speed rejected takeoff - needing a different technique to high-speed rejected takeoffs.

Anti Skid On
16th Aug 2021, 23:31
Searched but couldn’t find a thread on this.

Brisbane VH-VFF 23 October 2020

25 mm screwdriver bit damages engine after being there for around 100 flights

ATSB report
https://www.atsb.gov.au/publications/investigation_reports/2020/aair/ao-2020-058/

No injuries. ‘Only’ damage to an engine.

Thought it interesting the pilots mentioned the ‘startle’ factor - real world being both louder and with more vibration, than a sim. Also they had never practiced a low-speed rejected takeoff - needing a different technique to high-speed rejected takeoffs.

Would the screwdriver bit be magnetic, and could this have been stuck somewhere because of that?

Sue Ridgepipe
17th Aug 2021, 00:06
I would have thought low speed RTO would be part of the recurrent training matrix?

Veruka Salt
17th Aug 2021, 00:08
I recall a QF767 losing an engine on takeoff out of SYD due an Apex Bit finding its way into bleed ducting. Sneaky little things.

Global Aviator
17th Aug 2021, 00:51
Did the Capt just say screw it, don’t want to work today. :8

DogTailRed2
17th Aug 2021, 05:57
I recall reading an AAIB report about a 737 (possibly, I forget) out of Gatwick suffering a similar problem after someone left a spanner in the engine.
I think on that occasion the aircraft got airborne.

Lookleft
17th Aug 2021, 07:01
This is from the Safety First magazine about low speed aborts. Airbus recommendation? Practice in the sim.

5. Conclusion
This in-service incident illustrates the challenges associated with containing the sudden asymmetry resulting from engine failure during the first seconds of a take-off acceleration. However it is possible to maintain directional control by reacting immediately and in a coordinated manner:
q Thrust levers are closed
q All reversers are selected (even if designated as an MMEL item)
q Apply up to full opposite rudder pedals until directional control is regained
q Braking may be symmetrical or differential as needed to complement steering
q Steering hand-wheels may be used when taxi speed is reached.
Being in a position to effectively respond implies that both pilots have adjusted their seat such as to be in a position to simultaneously apply
full rudder and full brakes on the same side if required. Effective response also relies on crew training. Therefore Airbus supports Operators including RTO’s
scenarios in the recurrent training. The engine failure should be unexpected and introduced at speed well below V1. Such scenarios would address simultaneously the seat adjustment and the coordinated response
to the sudden asymmetry.

The problem apparently is harder braking gets applied in the direction of the divergence.

Fonsini
17th Aug 2021, 16:12
I thought that tool inventory control for aircraft maintenance had expectations on a par with surgical instruments in an operating theater. Everything is checked out and inventoried back in before any work can be signed off.

das Uber Soldat
17th Aug 2021, 23:39
This is from the Safety First magazine about low speed aborts. Airbus recommendation? Practice in the sim.



The problem apparently is harder braking gets applied in the direction of the divergence.
Below 72kts the autobrake doesn't activate in a reject. If you're used to doing RTO's above that speed (and they are), then the fact the thing isn't braking probably would catch you out for a second.

krismiler
18th Aug 2021, 03:03
Low speed reject is much harder, depending on the nature of failure, speed of occurrence and reaction time, you might be lucky to keep it on the runway.

https://www.skybrary.aero/index.php/A306,_Stockholm_Sweden,_2010

Rug
18th Aug 2021, 05:59
Uber, your point is correct and the startle effect caused will only serve to exacerbate the more fundamental technical issue that Lookleft refers to.

A low speed RTO caused by engine failure or asymmetric setting of takeoff thrust causes significant yaw surprisingly quickly. It's very difficult to steer out of it while applying effective differential braking at the same time.

Having trained for both of these scenarios in the sim on a slush covered runway with medium/poor braking action I can say it's very difficult to prevent a runway excursion. Extremely valuable training, the exposure to it will hopefully stand in good stead if ever required.

MJA Chaser
18th Aug 2021, 07:07
I thought that tool inventory control for aircraft maintenance had expectations on a par with surgical instruments in an operating theater. Everything is checked out and inventoried back in before any work can be signed off.

Yes, and errors occur in the medical world as well.