Seaplane crash into the Indian Ocean, Rottnest Island, W.A. - 07/01/2025

[onetrack]

Not much by way of news developments. I still don't believe the aircraft hit Phillips Rock. It may have crashed into submerged rocks not far out from Phillip Rock.

All the signs point to a stall on takeoff, it was struggling to make adequate airspeed once it left the water, and the port wings vicious drop points to a stalled wing.

 

Whether that was because there was inadequate power being produced by the PT6A, or because of a piloting failure, is yet to be found.

There's media fanfare about the aircraft being a "brand new plane", but the records don't show it as brand new, it was manufactured in 2016. It was "brand new" to the current owners, Swan River Seaplanes.

 

The aircraft was built in Aug 2016, initially registered to Wells Fargo Bank as N7129S, then de-registered and purchased by Whitsunday Air Services in late Sept 2016 and re-registered as VH-WTY. Ownership of the aircraft was transferred to Swan River Seaplanes, only a bit over a week ago.

 

There are some interesting points being raised in discussion. The maximum "demonstrated" crosswind speed listed by Cessna for the Amphibian, is 20kts. However, the POH says -

 

"Demonstrated Crosswind Velocity is the velocity of the crosswind component for which adequate control of the airplane during takeoff and landing was actually demonstrated during certification tests. The value shown is not considered to be limiting." 

 

Despite the above, the takeoff of the aircraft in the crash was in pretty choppy water (the stated wave height limit is 61cm), and the local indicated wind speed of 25-27kts with gusts to 31-34kts certainly made the takeoff riskier than any smooth water, light wind takeoff. The operators use Thompson Bay because it's partly sheltered from Rottnests winds, which are pretty fierce in the afternoons.

 

Takeoff weight with 7 pax should've posed no overload potential, the Amphibian is capable of carrying 10-14 pax, according to the specs.

 

A second interesting point is the seatbelts. The pilot and co-pilot seats are fitted with 5 point harnesses. The pax only get lap-sash style belts. I would've presumed the uninjured survivor is likely to be the pilot, with his superior belt security - but I may be wrong.

 

A third interesting point is that many aircraft operators over water, insist that crew and pax undergo training to extract themselves from submerged aircraft after ditching and crashes. It's called Underwater Egress Training, and is compulsory as part of OH&S in many corporations where employees work out to sea.

It's long ago been proven that may people (pilots and pax) survive crashes into the water, but then drown when they become disoriented under water, and caught inside a sinking fuselage. You generally get a couple of minutes to escape a sinking aircraft, enough time to orient yourself and make it to the surface (if you're able to still move, of course) - provided you have UE training.

 

I don't know if any underwater egress basic advice is given to pax on seaplanes, but I would expect it should be - comprising a more comprehensive level of advice, as compared to the escape advice on land, is given to pax on commercial flights.

[marshallarts]

Quote

 I would've presumed the uninjured survivor is likely to be the pilot, with his superior belt security - but I may be wrong.

Sadly, reports are confirming that the pilot is one of the deceased.  Egress from a sinking Caravan would be nightmarish - it's very cramped in there, and even though this one wasn't full, anyone would have huge problems getting out.  Most of the passengers were apparently over 60, which would only make it even harder.  I think there is a separate pilot door, but he/she would of course need to be conscious/capable to make use of it.

[onetrack]

Yes, that news that the pilot is one of the deceased is correct. A major update in the link below.

 

Three confirmed dead in Rottnest plane crash

THEWEST.COM.AU

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Premier Roger Cook has confirmed three bodies have been recovered from the wreckage of a seaplane which crashed off Rottnest Island on Tuesday.

 

[marshallarts]

One surprising thing (in a good way) is that one passenger got out of this completely uninjured.  I'm speculating he might have been sitting in the right seat, next to the pilot.  If there is a door on that side too, he would have had by far the easiest exit from the aircraft.  And the way it went into the water, on the left side of its nose, may have protected him a bit from the initial impact.  Plus the better seat belts there too.  I guess this will come out in time.

Edited January 8 by marshallarts

[kgwilson]

Looking at the video the Caravan appeared to struggle to gain speed during the takeoff run and it is likely the floats kept digging in to the choppy swell as it progressed slowing it noticeably. I think the pilot raised the nose similar to a max performance takeoff on land to try and keep the floats digging in to the waves ahead and so get up enough speed to get airborne. Once airborne the aircraft pitched up and then the aerodynamic stall became inevitable as it was on the verge of stall and in ground effect. Possibly the pilot wanted to make sure he was well clear of the waves as soon as he became airborne and kept a fair bit of back pressure on the yoke in the belief that there would be enough power to overcome this.

 

This of course is just one possibility. I think the hitting the rock theory can be now dismissed.

[onetrack]

Many times, it's simply the luck of the draw that determines whether people survive air crashes. Being seated in the rearmost seating appears to enhance your chances of survival in most cases, unless it's head-on into cumulus granitus.

[marshallarts]

21 minutes ago, kgwilson said:

I think the hitting the rock theory can be now dismissed.

I tend to agree.  From what I've seen it's only the police saying this and I wish they wouldn't, because I don't think it's established beyond doubt.  In one of the videos, when the aircraft banks left before impact, both floats are visible and both look intact.  If it had hit a rock, I'd think at least one of the floats would be severely damaged, possibly even torn off.  It's not good quality video, but I don't see that.  I've seen some pics of a badly-damaged float that was brought ashore, but that could have been caused by the impact with the water.  Lots more to learn here.

Edited January 8 by marshallarts

[onetrack]

The ATSB is seeking crash witness information on their site, they have a specific webpage set up for witnesses to provide details.

 

https://www.atsb.gov.au/media/2025/rottnest-island-cessna-208-accident

[facthunter]

It looks like being too slow and getting above ground effect. There could have been windshear or a gust/ wind change. That's all it takes.  Nev

[FlyBoy1960]

37 minutes ago, onetrack said:

The ATSB is seeking crash witness information on their site, they have a specific webpage set up for witnesses to provide details.

 

https://www.atsb.gov.au/media/2025/rottnest-island-cessna-208-accident

We should all go there and fill in the details, we have all witnessed the video, so that's almost as good as being there.

 

We ALL have an opinion on the cause of the accident which can save the ATSB doing a costly investigation. 

 

I love how the Internet saves me so much time !

[facthunter]

They are looking for "More" video or information. NOT our opinion of what caused it, based on what is already available.. It SHOULD have had plenty of power..  Nev

[red750]

Remember -

 

 

[facthunter]

Entirely different aspect to the CASA request.  Nev

[onetrack]

There's one factor that has come out of this crash that has made a big difference to the outcome - and that was the fact that recreational boaters were nearby, and on the scene within a minute, and helped rescue survivors from the wreckage.

I note that Col Blanch, the W.A. Police Commissioner made reference to this and expressed great appreciation towards the boaties involved. These people have possibly made a substantial difference to the final number of fatalities by grabbing the pax that were within reach of the surface.

The aircraft sank in 8 metres of water, but not very far away, the water is considerably shallower (3-5M), and there's a curved section of shallow rock called Natural Jetty, that runs from the Island to Phillip Rock.

The Natural Jetty rock formation is fully exposed at low tide, except for about a 50M section that stays underwater. The C208 took off at what appears to be high tide.

 

In addition, Phillip Rock used to be much higher and larger, but during WW2, when the Military controlled Rottnest Island (there are large ex-military barracks there), and Rottnest was being used as "first line of Naval Defence" (with the impressive 142 tonnes, 9.2" Naval gun still in place on Oliver Hill), a decision was made by the military that Phillip Rock posed an enemy visibility threat and needed to be lowered!

 

Accordingly, the Rock was blasted with a substantial number of artillery shells, which reduced the Rocks height to only about a third of its original height! All that rock blasted from Phillip Rock, now litters the area around the rock.

 

Photos - 1.  Original Rock size (prior to WW2)

 

2. & 3.  Views of the Rock today from (2) the West and from (3), the NE.

[onetrack]

The aircraft has been recovered today and taken to the mainland. The ATSB says the wreckage will be transported to Canberra for complete examination.

 

The wind and wave conditions today were vastly better than on the day of the crash.

 

Wreckage recovered as ATSB investigators piece together moments before Rottnest seaplane crash - ABC News

WWW.ABC.NET.AU

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The wreckage of a seaplane that crashed off Rottnest Island on Tuesday afternoon, killing three people, has been pulled from the water and taken back to the mainland for further investigation. 

 

[BrendAn]

2 hours ago, onetrack said:

There's one factor that has come out of this crash that has made a big difference to the outcome - and that was the fact that recreational boaters were nearby, and on the scene within a minute, and helped rescue survivors from the wreckage.

I note that Col Blanch, the W.A. Police Commissioner made reference to this and expressed great appreciation towards the boaties involved. These people have possibly made a substantial difference to the final number of fatalities by grabbing the pax that were within reach of the surface.

The aircraft sank in 8 metres of water, but not very far away, the water is considerably shallower (3-5M), and there's a curved section of shallow rock called Natural Jetty, that runs from the Island to Phillip Rock.

The Natural Jetty rock formation is fully exposed at low tide, except for about a 50M section that stays underwater. The C208 took off at what appears to be high tide.

 

In addition, Phillip Rock used to be much higher and larger, but during WW2, when the Military controlled Rottnest Island (there are large ex-military barracks there), and Rottnest was being used as "first line of Naval Defence" (with the impressive 142 tonnes, 9.2" Naval gun still in place on Oliver Hill), a decision was made by the military that Phillip Rock posed an enemy visibility threat and needed to be lowered!

 

Accordingly, the Rock was blasted with a substantial number of artillery shells, which reduced the Rocks height to only about a third of its original height! All that rock blasted from Phillip Rock, now litters the area around the rock.

 

Photos - 1.  Original Rock size (prior to WW2)

 

2. & 3.  Views of the Rock today from (2) the West and from (3), the NE.

paused a threat. more like target practice😉

 

[facthunter]

The winds and choppiness on the surface may have  made  a lower speed lift off desirable/ necessary and there is also a possibility of a float seam opening and taking water. The plane certainly wasn't at max weight. There's no VMC (a) consideration only stall speed with a Caravan When you're SLOW, ground effect is your friend. IT also sank very quickly..  Nev .

[onetrack]

A couple who survived the crash have thanked rescuers, emergency services and the ATSB investigators - and have made a point of saying they almost certainly owe their escape from the sinking aircraft to the detailed instructions provide by the deceased pilot, on how to operate the emergency exit door. I would have to opine, their escape from the sinking wreckage was also due to the fact that they took the trouble to listen to the instructions carefully.

 

Perth couple who survived Rottnest Island plane crash give thanks to rescuers, medical personnel - ABC News

WWW.ABC.NET.AU

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The Perth couple who survived a plane crash off Rottnest Island last week, which killed two tourists as well as the pilot, thank rescuers and medical personnel.