4 fatal - crash nw of Waterloo ON Aug 24 2012

[Rookie50]

Thats right. Being a low timer took my brains away. For the record, i (try to) treat my flying with as much professionalism, care and studying as those with 20 times the experience, that is very seriously. Not all low timers are cowboys.

I can speculate what happened here just as easily as anyone. Its not that tough, even for this low timer. I just choose not too, on this thread. That's it. As I said, the issues discussed may have validity, but you cannot definitively apply them to this accident, so is better to start a new thread then on those broader issues. I do respect the motives and experience of the high time posters, to reduce accidents.

[cgzro]

deal with as TSB has. There are no CVRs, no BLACK BOXES. They have a few photos of an impact site. Nothing more. Nothing less. It's pretty obvious what happened here.

I believe they will do toxicology and have radar traces. They will have maintenance history of the plane, driving records etc of pilot..., they will be able to tell position of all controls at impact, depth of impact vs soil density, angle of impact etc.

So I think they have more to go on than we do here.
That may not change end result but they certainly have much more.

[Doc]

deal with as TSB has. There are no CVRs, no BLACK BOXES. They have a few photos of an impact site. Nothing more. Nothing less. It's pretty obvious what happened here.

I believe they will do toxicology and have radar traces. They will have maintenance history of the plane, driving records etc of pilot..., they will be able to tell position of all controls at impact, depth of impact vs soil density, angle of impact etc.

So I think they have more to go on than we do here.
That may not change end result but they certainly have much more.

I think you've been watching too much TV. CSI has gone to your head. Perhaps they'll find an alien presence? It'll be a year and a half, at least......meanwhile, back at the ranch.....

[North Shore]

So, Cat & Doc, back at the ranch, what did happen outside Waterloo? (Apart from Napoleon being beaten - were you there for that Cat? )

[Cat Driver]

From what the picture shows the airplane impacted the ground in a flat attitude at a high rate of descent.

The most probable cause woud be a flat spin.

How the airplane ended up in a flat spin has not been determined as far as I know.

Maybe the investigtion will shed further light on the cause such as pilot incapatitation.

What do you think happened North Shore?

[Doc]

Our pilot was a little young for incapacitation. More likely a spin in an out of CG envelope aircraft. Impact certainly indicates a flat arrival in a level attitude. Probably a flat spin as Cat says. The fact the flight went over the Falls, and ended up in the practice area weighs heavily in the direction of some deliberate "air work".
Unless a toxicology report comes back positive, I think that's about it. If there was something on the tox report, I would hope that would come out long before the final TSB report. I think we'd know already.
I hope this accident will give pause to others.

[Taiser]

Our pilot was a little young for incapacitation. More likely a spin in an out of CG envelope aircraft. Impact certainly indicates a flat arrival in a level attitude. Probably a flat spin as Cat says. The fact the flight went over the Falls, and ended up in the practice area weighs heavily in the direction of some deliberate "air work".
Unless a toxicology report comes back positive, I think that's about it. If there was something on the tox report, I would hope that would come out long before the final TSB report. I think we'd know already.
I hope this accident will give pause to others.

I've been involved with investigations like this. My outfit assists TSB when they come to do an investigation in our areas. I've had the misfortune to help out at maybe a half dozen incidents in the last 10 years or so, quite a few more if you count the non-fatal ones. Although they are all tragic, I find them intriguing... some are pretty complicated puzzles.

They will do full autopsies. The pilot will be checked for any type of incapacitation such as heart attack, stroke etc. They will do a full drug screens on toxicological samples and check for any alcohol consumption. This is not done under any suspicion but as a routine part of the investigation and becomes critical if anything is found to be amiss, especially with insurance companies and such. They usually shell out big bucks for investigative reports. Standard toxicology test from the Center of Forensic Sciences usually takes about 3 months. If a rush is put on (unlikely in this case) results can be had in a few days.

Many would be surprised at what you can find out from the instrument panel, especially when it survives the impact. Good chance that most of the instruments have "damage" marks from the needles in them at the time of impact. You can usually find out what the airspeed was, what the vertical speed was, speed of the engine etc... Motor will be torn down to find if anything queer was going on, as well as most of the plane...fuel will be examined for water or whether it was getting to the engine, etc... all this is what takes time...

[North Shore]

From what the picture shows the airplane impacted the ground in a flat attitude at a high rate of descent.

The most probable cause woud be a flat spin.

How the airplane ended up in a flat spin has not been determined as far as I know.

Maybe the investigtion will shed further light on the cause such as pilot incapatitation.

What do you think happened North Shore?

I'll agree on the what (flat spin), but the why remains to be seen - and I don't think that we should be jumping to conclusions about that. Now it may well be that the PIC purposely induced a spin without first thinking about it - but there could be other reasons for the spin that aren't immediately apparent...

[GyvAir]

Many would be surprised at what you can find out from the instrument panel, especially when it survives the impact. Good chance that most of the instruments have "damage" marks from the needles in them at the time of impact. You can usually find out what the airspeed was, what the vertical speed was, speed of the engine etc...

How directly 'head-on' would a collision have to be for needle marks to show on the instrument faces? In an apparent flat landing such as this, would it be reasonable to expect no marking to occur, as the needles would presumably be driven downwards instead of forward?

[Taiser]

There has to be some angular momentum but even a flat spin still has a bit of an angle on it. The needles are sitting in front of the instrument face by fractions of an inch...It doesn't take much, but in some cases you don't get anything, in others it only affects an instrument or two. Lots of variables but all the ones I've seen have always had at least one or two impact marks from the needles on them although I've never been to a scene like this one where there is so little damage to the surrounding area, but I'm still guessing they will get something...

[cgzro]

Probably a flat spin

I've only ever tried flat spins in aerobatic planes.

In C172's and 150's I've never gone full power in a spin or aggrevated the spin with aileron or elevator as would be normal for flat spin entry so have no idea how they react. Do they really flatten up that much under full power in the spin?

[CpnCrunch]

According to this, Cessna engineers say it's "virtually impossible" to flat-spin a 172:

http://www.aopa.org/special/microsoft/a ... n9710.html

So what does 'virtually' mean? I'm guessing you need to have the C of G pretty far aft for a start (I wonder if it needs to be beyond the aft limit, or just outside the utility range?) I'm also guessing that it wouldn't ever happen by accident.

[cgzro]

Likely insufficient power and down elevator to really go flat?

[Colonel Sanders]

In C172's .. do they really flatten up that much under full power in the spin?

In a left-yaw upright spin in a 172, you can pick up
the nose with power - if you can keep it in the spin!
It has a nice metal prop with good gyroscopic precession.

Hope this data point doesn't offend the oh-so-sensitive
AvCanada experts.

I still don't see what the huge deal is with a flat spin, either
upright or inverted. I always found the accelerated spin
(upright or inverted) much more interesting than the flat,
but I guess I just don't know very much about spins.

[Cat Driver]

In the interest of discussing possibilities of how this accident happened we should look at it from a logical viewpoint to start.

Logic would dictate that a Cessna 172 would have to lose approximately 50% of its airspeed to get from cruise flight as in sight seeing to the stall speed that is necessary to start a spin.

If we knew how the airplane lost 50% of its airspeed it would give us a better insight into how it ended up contacting the ground at a high rate of descent with no forward movement as evident from the pictures.

[North Shore]

In a left-yaw upright spin in a 172, you can pick up
the nose with power - if you can keep it in the spin!
It has a nice metal prop with good gyroscopic precession.

Hope this data point doesn't offend the oh-so-sensitive
AvCanada experts.

I still don't see what the huge deal is with a flat spin, either
upright or inverted. I always found the accelerated spin
(upright or inverted) much more interesting than the flat,
but I guess I just don't know very much about spins.

Give your head a shake, Sanders, and come back to earth... You've got what, 40? years of flying experience, starting off in some squirrely Maule, a load of aerobatic experience (that you are, presumably, good enough to get paid for) and now a stable of Pitts' to play around with. Yes, I'll agree, that flat spins, for you, are easy to recognise and recover from; for the rest of us, not so much. And, in the case of this poor bugger outside Waterloo, with 200-ish hours and a 172, well it was a BFD. In fact, I'd bet for about 99% of us who were unlucky enough to get ourselves into that spot, that it would be a huge deal...

For a smart guy, you really make me wonder sometimes about your contact with the real world...

[CpnCrunch]

Even NASA test pilots couldn't recover from some flat spins where the C of G was too far back. I'm guessing CS is confusing a flat spin caused by power/elevator input, as opposed to a flat spin caused by an aft C of G. It stands to reason that if the flat spin is caused by pilot input then you can probably/possibly reverse it if you know what you're doing, whereas if the C of G is too far back then even expert pilots might not be able to recover. I'm pretty sure even CS hasn't spun a plane outside C of G limits.

I think we know for sure this airplane was being operated outside the utility category, so the C of G would have been outside limits for spins.

[Colonel Sanders]

I'm pretty sure even CS hasn't spun a plane outside C of G limits

Like I'm going to touch that trap.

Anyways, just because a certified aircraft is outside the
establish W & B limits approved for spins, doesn't mean
that it is necessarily totally unrecoverable from spins.

It may just mean that the FAA isn't happy with the
control inputs required to recover from the spin.

For example, in a flat spin to the right, a blast of
throttle will cause the nose to dip if you fly behind a
Lyc/TCM/Franklin, both due to gyroscopics and
increased rudder effectiveness.

Even in a flat spin to the left, you might still experiment
with a blast of power to try to lower the nose. Even
though you are fighting gyroscopic precessions, flat
spins are often oscillatory in pitch, so if you time it
right, you might be able to lower the nose.

The thing to think about upright flat spins is that even
though it's terribly tempting to push the control yoke
all the way in to try to lower the nose, remember that
what you are doing is lowering the elevator and blanking
more of the rudder underneath it. Basically, you're making
a smaller rudder, and that's not good when what you
want is the biggest rudder possible to stop the yaw.

Remember what I said about the FAA not being happy
with the flight control inputs required to recover?

That's why inverted spins are so much safer than
upright spins - all of the rudder above the elevator
is in clean air, so it has far more authority to stop
the yaw when you apply full opposite rudder. I
routinely exit inverted spins below 1000 AGL, because
they are such pussycats.

If you have a big enough rudder, anything is possible.
Rob Holland in his MX2, does a very neat approach
to landing at the end of his airshow routine - an
upright flat spin to lose energy, to short final. Needless
to say, the MX2 has enormous rudder and elevator
surfaces!

This post was 100% factual and was intended to
educate, but I'm sure it will enrage various people.
Oh well.

[Colonel Sanders]

One last data point: please don't fixate on W&B
limits wrt spin recovery behaviour.

I could give you two identical aircraft, sitting beside
each other on the ramp.

One would have the W&B with approved spin limits,
but due to high polar moment of inertia, would have
very nasty spin recovery behaviour.

Another would have the W&B outside the FAA approved
spin limits, but due to very low polar moment of inertia,
would have very benign spin recovery behaviour.

PMI is just as important as W&B to spin/tumble behaviour!

Feel free to attack me on this - I am only a graduate engineer
as well as an ATPL as well as an experienced airshow pilot,
and I'm sure I don't have your qualifications, education,
knowledge or experience.

you really make me wonder sometimes about your contact with the real world

Thanks, that's good advice - I'll try to spend more time at
the airport.

[SeptRepair]

So whats your take on Art Scholl? Seems one of the more talented aerobatic pilots himself could not get out of a flat spin with extra weight.

[slam525i]

Logic would dictate that a Cessna 172 would have to lose approximately 50% of its airspeed to get from cruise flight as in sight seeing to the stall speed that is necessary to start a spin.

I spend a lot of my precious rental-airplane money on taking friends to do city tours over Toronto, usually at night. I don't know what others do, but I usually slow her down when doing the city tour. I'm usually down to 70-80 kts when doing the tour, and I drop a little flap to give myself more margin while keeping one eye on the ASI (the other is on the altimeter). I want to slow down for a better tour but I also want to not screw it up, kill myself, drill a hole in a building, and ruin it for everybody else.

I can imagine that if they saw something interesting, slowed down and started orbiting it, the combination of low speed and turn could result in an accidental spin.

P.S. The folks at CYTZ are absolutely fantastic people. Very accommodating for skill-less PPLs like me, interfering with them trying to get Porters in and out, especially when I ask to see if I can do a low-and-over.

[Colonel Sanders]

Art Scholl

A little background: He was an experienced airshow pilot
that died during the filming of Top Gun. I understand he
was filming a flat spin sequence in a Pitts S-2A over the
ocean, and the wreckage was never recovered. He radioed
that he had a problem, and that's it.

My personal suspicion at the time (and still is) was polar
moment of inertia. Cameras in 1985 were not the tiny,
light HD digital units we have today. If it was mounted
with a long arm ...

There are other possibilites, such as the camera disrupting
airflow over the rudder/elevator.

Or, maybe the camera came loose, and interfered with
the rudder/elevator.

I doubt we will ever know.

Data point: a friend of mine was spinning his Pitts S-2C
with the huge two-place canopy (same as S-2A) entirely
removed, for jumper dumping (don't ask):



Anyways, he found that removing the canopy make
a huge (and unpleasant) change to the spin characteristics
of the aircraft. I won't go into the details here, but it
scared the sh1t out of him.

[cgzro]

Art Scholl likely removed the canopy too. Much better optics for a camera in free air and likely impossible to fit in a big camera with canopy on anyway. Ive heard lots of comments about very different spin charactistics with the 2 vs single canopy options too so smallish changes is fuse profile have profound effects in some a/c
but that seems of course unlikely to be relevant in this case.

[cgzro]

I think we know for sure this airplane was being operated outside the utility category, so the C of G would have been outside limits for spins.

As long as he was still within norma category then it should be certified recoverable up to one turn , within one turn with standard inputs at least thats my understanding of the certification. Utility they check more stable established modes etc.

So unless he was outside rear normal he had a demonstrably recoverable plane, no?

Of course Im not suggesting its safe to spin in normal category simply pointing out that certification requires spin recovery be possible so given enough altitude it should not be instant unrecoverable flat spin within normal. Aft of normal of course nobody methodically has tested it so no guarantees.

[jamesel]

Disclaimer - continuing a conversation, not pointing fingers or claiming to conclusively prove any accident cause.

CGRZO is correct - FAR 23 for the NORMAL category requires testing to prove recovery from a one turn or 3 second spin (whichever is the longest) with normal recovery procedures. Interestingly, it must be impossible to obtain uncontrollable spins with any use of the flight or engine power controls. Doesn't mean it can't go flat or accelerated, just that you have to be able to recover, if you know how. Sometimes, easiest to return the aircraft to a normal spin, if it will, and recover from that. In a "normal/non-aggravated" spin, FAR23/CAR523 "Normal Category" rules require recovery in no more than one additional turn.

So if someone demonstrates anything past 1 turn, (and it can rotate fast) they're now a test pilot, & please don't use live ballast. The first time the plane doesn't slide out of a spin as soon as the pro-spin control inputs are relaxed usually comes as a suprise to most pilots.

The only time I have experienced a spin in a 172 loaded to the normal limit, the conditions were:
1) Non-Intentional!
2) Checking out a licenced pilot (that gives 99% of all instructors a shiver down their back, knowing what kind of randomness in skill levels that implies)
3) Normal category - 4 people, reduced fuel
4) 40 Flap!

Classic entry - Student a little high & fast on base, overshot final, chopped power, pulled on full flap, started the turn, kept it shallow with aileron, and booted it around with rudder. It's a 172 fer chrissakes, so I played it cool & had just enough time to say "Ya know, if you keep doing this we're going to ...", and before I could get "spin" out, it did. Boy Howdy, I'll tell you, it snapped into it. I was current in spinning on C-150s/172s/177s/Citabria & Chipmunk, and it stepped right out & got moving faster quicker'n any of them. The ground unexpectedly rotating 700' below motivates a person. I crisply applied full opposite rudder, and the control column hit the forward stop before the rotation stopped.

I'm aware the accident airplane did not have flap extended, but, MAN, that spin wasn't anything like the 172 spin I was used to. A fellow not current or prepared for different spin characteristics could easily be overwhelmed, especially if it was allowed to develop for a turn or two. Mass polar distribution really affects the way any airplane spins.

Edited to add "Normal Category"