February 2023 crash of a Boeing 737-300 Air Tanker in Australia

[W5]

Accident report:

The February 2023 crash of a Boeing 737-300 Air Tanker in Australia occurred when the aircraft was in a low energy state prior after a fire-retardant drop. The aircraft collided with an undetected ridgeline at an elevation of about 222 feet and was consumed by fire. Both pilots survived.
The ATSB published its final report into the accident, stating that the operator and tasking agency had not published a minimum drop height for large air tankers. This resulted in the co-pilot, who did not believe there was a minimum drop height, not making any announcements about the aircraft’s low energy state prior to the collision.

https://www.atsb.gov.au/publications/in ... o-2023-008

[digits_]

The aircraft collided with an undetected ridgeline at an elevation of about 222 feet and was consumed by fire. Both pilots survived.

How?

I mean, great, wonderful, but ... how

Reading the report, they even walked out.

[karmutzen]

Terrain wasn't like BC, it was flat, scrub vegetation. Low speed, low rate of closure impact.

[pelmet]

Unless it is somehow mandatory, it seems very foolish to do these drops with flaps 40. That is a huge amount of drag and tales quite a bit more thrust to stabilize on a descent. Is there really any reason to not use only flaps 30.

I haven't read the report thoroughly but I did not see any discussion about this obvious fact.

[digits_]

Unless it is somehow mandatory, it seems very foolish to do these drops with flaps 40. That is a huge amount of drag and tales quite a bit more thrust to stabilize on a descent. Is there really any reason to not use only flaps 30.

I haven't read the report thoroughly but I did not see any discussion about this obvious fact.

Isn't that the whole point? You want lots of drag because you want a higher power setting, which means in a go around the engines don't need to spool up as much. And you can partially raise the flaps and have instant excess power. Also note the gear is usually up during a drop, so the only way to get drag is via the flaps.

[bigredone]

How do you know when anyone from Coulson is lying? Yeah, you know the punch line. Total BS as far as unknown terrain and FO not saying anything because blah blah blah. Typical of these idgets to deflect, blame, lie, coverup etc. They are the first ones to throw anyone else under the bus to cover the total incompetence of that operation. If they budgeted half as much for training and maintenance as they do for their media propaganda then maybe these things wouldn't happen every second week. And remember, you are only hearing tip of iceberg problems that they can't hide.

[pelmet]

Unless it is somehow mandatory, it seems very foolish to do these drops with flaps 40. That is a huge amount of drag and tales quite a bit more thrust to stabilize on a descent. Is there really any reason to not use only flaps 30.

I haven't read the report thoroughly but I did not see any discussion about this obvious fact.

Isn't that the whole point? You want lots of drag because you want a higher power setting, which means in a go around the engines don't need to spool up as much. And you can partially raise the flaps and have instant excess power. Also note the gear is usually up during a drop, so the only way to get drag is via the flaps.

The reason for wanting a higher thrust setting on approach is due to a lag in thrust increase from low power settings that are close to idle. There will be plenty of ability to spool up quickly for a go-around at 30 flap with approach power set. And that is for a three degree descent. Waterbombing ops could be level flight or even a slight climb depending on terrain. It is from closer to idle thrust where delays in thrust increase occur. But high drag can lead to a quick loss of airspeed and a waterbombing flight is close to terrain with pilots likely spending a lot of time focussing on looking out the window. Windshear would seem to be more likely in wildfire conditions as well. I really wonder if how much benefit there is from 40 flap in a situation like this.

[Donald]

Unless it is somehow mandatory, it seems very foolish to do these drops with flaps 40. That is a huge amount of drag and tales quite a bit more thrust to stabilize on a descent. Is there really any reason to not use only flaps 30.

I haven't read the report thoroughly but I did not see any discussion about this obvious fact.

Isn't that the whole point? You want lots of drag because you want a higher power setting, which means in a go around the engines don't need to spool up as much. And you can partially raise the flaps and have instant excess power. Also note the gear is usually up during a drop, so the only way to get drag is via the flaps.

The reason for wanting a higher thrust setting on approach is due to a lag in thrust increase from low power settings that are close to idle. There will be plenty of ability to spool up quickly for a go-around at 30 flap with approach power set. And that is for a three degree descent. Waterbombing ops could be level flight or even a slight climb depending on terrain. It is from closer to idle thrust where delays in thrust increase occur. But high drag can lead to a quick loss of airspeed and a waterbombing flight is close to terrain with pilots likely spending a lot of time focussing on looking out the window. Windshear would seem to be more likely in wildfire conditions as well. I really wonder if how much benefit there is from 40 flap in a situation like this.

The details are in the report.

Idle thrust, descending, go around attempted at 57 feet.

Captain was the company chief pilot, FO had 100 hours on type.