C210 crash in Roma

[megle2]

CS your probably recalling the King Air 90 departing Wondai

There has been a number of bad accidents within a short distance of Roma at night particularly the B23 and B55 but there are others

[compressor stall]

Thanks, yes that's the one.

The fog of Grenache made me think it was Roma. Close enough, eh?

[avcraft]

There was a 55 Baron went in west of Roma around 1988 / 89? Then a very well known engineer from Longreach in a Mooney around 1996... Both inbound at night.

[Arm out the window]

If I read you correctly Centaurus, are you implying that if you nail the instruments (ie pitch), you won't get the illusion in a C210, but you would/could in something faster?

G'day CS,

I imagine he's just referring to the root cause of the illusion, ie longitudinal acceleration fooling the body into feeling that the real gravity vector is not pulling straight down, but from somewhere down and behind you, so you feel like you're falling over backwards and want to push to compensate.

More acceleration, worse illusion. I think it would still be possible to experience it to some degree even with moderate acceleration, though - haven't seen any figures to refer to a minimum rate to trigger an onset.

[MCKES]

The crash you are thinking of was a c90 at I believe Wondai.

[Dora-9]

More acceleration, worse illusion. I think it would still be possible to experience it to some degree even with moderate acceleration, though - haven't seen any figures to refer to a minimum rate to trigger an onset.

Despite this mere mortal never having flown the super equipment that Centarus is telling us that he has, and despite his clear disdain for this possibility, I would have thought the acceleration of a C210 with only two on board would have been conceivably sufficient to trigger this illusion.

[rocket66]

I tend to agree with Dora. It not only depends on the aircraft in question it also depends on other factors like his experience, if he had done any ifr flying, illness etc etc. Never good news to wake up to nonetheless.

Rocket

[Ixixly]

I would have imagined that a Turbocharged 210 with only 2 people on board would have been capable of a reasonable amount of up & go?

[VH-XXX]

I would have thought the acceleration of a C210 with only two on board would have been conceivably sufficient to trigger this illusion.

IF it was dark enough to trigger it?

[garrya100]

The image of the accident site could support that theory, it show what appears to be a low angle of contact at high speed. The wreckage trail was over 500m long (according to the news), and the image shows that the breakup occured mainly at the end of the sequence.

I would have though that an EFATO scenario would have shown the same sort of angle with a much shorter wreckage trail.

A question for the much more expirienced than I, could an initial over rotation on lift off exacerbate the illusion and thus disguise the fact the aircraft was actually settling?

[neville_nobody]

Airborne after first light should give you something resembling a horizon given that is severe CAVOK. I don't think disorientation should be an issue.

[A37575]

Despite this mere mortal never having flown the super equipment that Centarus is telling us that he has, and despite his clear disdain for this possibility, I would have thought the acceleration of a C210 with only two on board would have been conceivably sufficient to trigger this illusion.

The "super equipment" quip is a bit unfair. Nowhere in Centaurus comments warranted such sarcasm. However, in numerous Australian general aviation accident reports, where, in the absence of any evidence of technical malfunction that was the cause of an accident, the possibly contributory cause of somatogravic illusion is invariably mentioned. In other words it is a catch-all fall-back reason for an accident but without a shred of hard proof.

If, presuming all pilots - including airline pilots - are subject to such an insidious illusion at night or in IMC, then perhaps this warrants ATSB attention in the form of a survey to all licensed pilots to obtain hard data. That survey should include statements of aircraft type involved.

[ForkTailedDrKiller]

Is "somatogravic illusion" a fancy way of saying, "the aeroplane was allowed to descend back into the ground"?

Has happened many times before and will no doubt happen many times in the future.

There are not many new ways for a pilot to crash an aeroplane - we just keep re-using all the old ones!

Dr

[sheppey]

Many years ago a Convair 580 flew into the sea within seconds of lifting off from Auckland airport. Both pilots died in the accident. It was a dark night and once airborne the crew would have been on instruments. I don't know if the investigators considered they both could have been affected simultneously by somatogravic illusions.

But the investigators did find out that the copilot who was conducting the take off was on her first flight as handling pilot. Also in several previous flights the copilot's artificial horizon instrument was defective in that it displayed erroneous indications in roll and pitch attitudes. Not only that, but the instrument was left in place while awaiting a replacement. The situation had been like that for a few weeks.

The investigators asked other company pilots about their experiences of flying with the captain who was also the chief pilot. Take off's in the Convair required the use of take-off flap. Retraction of flap after take off was normally done above 500 feet due to the significant nose down pitching moment that was a characteristic as the flaps came in. Notwithstanding this characteristic, the captain was well known for his habit of selecting flaps up almost immediately after the gear was selected up and this was as low as 100 ft.

The investigation concluded that although the copilot had never flown the Convair - apart from observation flights - this was her first flight actually handling the controls. It was a night IMC departure with a known defective artificial horizon on her side. The action of the captain in selecting flaps up soon after lift off, would have caused a nose down change of pitch that may not have been noticed by the copilot faced with a faulty artificial horizon. To a new copilot this would have been an impossible task to pick the problem. The captain was at fault for putting her in a situation that would have taxed even a highly experienced instrument pilot.

The Convair 580 was a powerful aircraft with excellent acceleration during take off. Maybe somatogravic illusion was a contributory factor in the accident. But in this particular accident there were more compelling facts that came to light. Take your pick...

[Arm out the window]

Is "somatogravic illusion" a fancy way of saying, "the aeroplane was allowed to descend back into the ground"?

Not really, FTDK. Inattention to attitude would be the more likely cause for that one, I reckon.

Somatogravic is when you accelerate, and as well as being pulled down by gravity you are now pushed back in your seat. In the absence of a clear horizon, you now feel as if gravity is acting from somewhere behind you, ie it feels like you're falling over backwards. Also known as the 'pitch-up illusion'.

Natural response - push forward to make things feel more normal. Correct response, of course - get on the AI and set the correct climb attitude and get into your scan.

One I know of was when a solo 2FTS student in a Macchi on a night takeoff just flew into the ground - it was put down to somatogravic illusion and well discussed (although if you're not the flying pilot you can't possibly know for sure, I guess.)

[Dora-9]

The "super equipment" quip is a bit unfair.

Yes, on second thoughts you're correct - Centaurus, please consider the quip humbly withdrawn. However I think you're incorrect to say that it couldn't be this effect simply because you don't think the aircraft concerned had sufficient acceleration. How much acceleration is enough?

Is "somatogravic illusion" a fancy way of saying, "the aeroplane was allowed to descend back into the ground"?

Forky, the simple answer is no, and yes. The pilot pushes forward to overcome a perception (the somotogravic illusion) of rotating backwards, and the aircraft contacts the ground when it should be climbing away. But you could also argue that if he flew his instruments and ignored the sensations then he wouldn't allow the aircraft to descend back into the ground. I recall when I first got an instrument rating being told over and over again to ignore the sensations/fly the instruments. Good advice indeed, that was 45 years ago, and given the right trigger(s) I can occasionally still experience "the leans"!

[Lancair70]

As a young fella and at the time, under training for my MEIFR, (completed rating a month or so later) I departed YBTH to the north on a NVFR flight in the early hours, (4.30am local) solo in a C210 and quite vividly recall suffering somotogravic illusion, I definately felt like I was pitched way nose up. I forced my self to believe the instruments that I was in a 800fpm climb and accelerating quickly through 90knots, as I recall it took another minute or so until I was feeling like everything was normal and I was game to look away from the instruments
Being under training for my MEIFR I was, I guess in the best situation to realise it. I also feel all the crash comic stories I'd read over the previous 2 years or so helped. ALL student pilots should be reading these old mags as a MUST do when learning to fly, us older pilots should also re-read and learn from them.

[Wally Mk2]

Firstly I hope the family & friends left behind after this tragic accident can find some peace knowing that any sad event like this wakes us all up & we can refresh our tired minds to such illusions so that it doesn't happen to us.

This debilitating illusion is based on pitch as we all know & being so close to the ground in this critical stage of flight I think it's worth doing some research on the subject for yourself.

I had this very feeling bad one night out of YPID to the Sth in the old Dove. If it wasn't for the fact that the ground below me drops away to the beach some 80 ft or so I may not be here now! I swore that I needed to descend felt like I was gunna flip back & stall! I saw the ASI going balsitic & if anyone knows the old Dove the only way that could happen is in a dive! So I grabbed the ASI like it was a life jacket & held 80 kts or so 'till I was almost to the Moon!!!! I didn't get fixated on the AH as that inst can be very confusing when under duress I just referenced it to make sure my wings where fairly level.
What did I learn that night? What can we all learn (& lets use this C210 sad event as a learning tool)? KNOW yr PLANE. Know what it's capable of airspeed wise ROC wise where the trim needs to be for T/off. Adapt to the nosie the engine/prop makes under normal climb conditions.
Leave the bloody flaps & power alone 'till well above the ground at night & in poor external light conditions the donk can scream it's head off for a few seconds longer. The last thing ya wanna do is look away from that ASI whilst fiddling with the engine controls.
The ASI is a trend inst, it tells you a LOT of things, use the bloody thing like yr life depends on it!
Check what yr machine does when the suns out in good flying conditions when taking off. How many of us just sit there time after time during t/off & really not notice what's going on with our machine? Sure we know what to do it's almost a robotic experience when ALL yr senses are working to supply yr CPU (Brain) with info it ain't rocket science on a nice day BUT remove some of those cues (eyes the most important info gatherer) & that very same event you do repetitively all of a sudden feels like yr in another world!
The most important instrument to me was the ASI, that inst is several inst's rolled up in one. You can see in yr peripheral the AH if yr wings are fairly level.

Obviously all of the above is how I see it, what I used to do as I've done a LOT of single pilot driving at night out of & into some bloody black holes over the years in machines that are ripe for somatogravic illusions & the ASI has/was always my friend.

So again lets all learn from this rather than bag each other for armchair flying.

Wmk2

[Keg]

There was a TB10 flown by a couple of foreign students that speared in at Ceduna some years ago due to somotogravic illusion. Wouldn't say a TB10 was hot ship either!

Except it wasn't really a somatogravic illusion. They were further away from the airfield than is normal with those sorts of prangs and they'd already commenced a turn for Adelaide. Rather than impacting nose down in an 'up and over' type deal they more or less flew on a gradual descent into the ground. IIRC, the ATSB report didn't think somatogravic illusion as being the likely cause.

Finally, it was a Trinny rather than a Tobago so acceleration may have been a bit of an issue but not something that the ATSB thought relevant.

[aroa]

The Convair 580...

...was a very powerful aircraft .... Sheppey.
I havent read any NZ report on that accident but a NZ frund mentioned that there were prop marks from one side, on the runway and airfield before the bay where it speared in.
Acceleration probs?.... or just did it just get away from her on the take-off?

Whatever..a tragic outcome... as with the 210 ....and all the others this week. Very not good.
RIP.