View Full Version : Question about recent fatal accident

1st Apr 2008, 17:37
A recent plane crash in Canada was caused by instrument failure, according to preliminary findings of the Transportation Safety Board. The Board found that "pilot Regan Williams was virtually flying blind after both the autopilot and gyroscope (sic) malfunctioned during a flight early last Friday."

Here's my question. If the gyro horizon fails can you not use the turn and bank indicator along with the other instruments? Isn't the turn and bank driven separately than the gyro horizon? I seem to recall that Lindbergh flew the Atlantic without a gyro horizon. Thanks in advance.


1st Apr 2008, 21:19
I am afraid that "limited panel" flying is a thing of the past. I dont think it is taught anymore, except maybe in the military.

1st Apr 2008, 21:46
A turn and bank indicator only shows "rate" of turn. The Cessna aircraft I learned on had an electric one with a mini airplane on it. As you banked you put the wing tip of the little airplane on an index and then knew you were in a standard rate turn. The problem is that this instrument does not show "bank" per se. In turbulence the wings rock and roll all over the place. It is a difficult skill to acquire to fly by turn coordinator. (turn and bank) only. For example if the pilot gets in to a steep spiral it can be very difficult to use only a turn and bank to recover.

1st Apr 2008, 23:18
Partial panel was standard RAF training. The turn needle, ASI and altimeter can be quite effective but without training it would be very difficult. A turn needle over-reads like crazy unless only 1 g is applied to it.

I once pulled 6.5 G (within aircraft limits) during a "no horizon" UP recovery on an IRT and blacked out my IRE. He never admitted it and I still passed! Mind you, I'll bet he never gave another partial panel UP from inverted at the top of a barrel roll :E

1st Apr 2008, 23:42
.. on a similar line, when I finished my PPL, I did 8-10 hours under the hood aerobatics on limited panel ... which I consider to be one of the best investments I've ever made .... apart from which it was great fun.

galaxy flyer
2nd Apr 2008, 00:02

It has been a long time since I even contemplated needle, ball and airspeed, but can any acro be accomplished partial panel? For example, a roll properly done should not show any turn rate. A loop should have no turn until 90 degrees of pitch, then lots of turn!!

In the '70s, the USAF only discussed partial panel, it wasn't a eval item. We always had a "peanut" gyro until I got into the C-5, where 3 INSs and 2 AIs were thought "good enough". Until a friend of mine had to do a partial panel climb to "on top". VFR to another airport where VMC existed.


2nd Apr 2008, 04:10
If this was a failed artificial horizon, it can be very disorienting. Once you have determined that the AI has failed, it is best to cover it up. There are actual circular pieces of bathmat-like pads that can be bought at some pilot shops designed for this but most pilots don't have these available. Something as simple as a piece of paper may be able to fit in place. Different planes can vary on what powers the gyros.

2nd Apr 2008, 04:47
The article did not mention if the airplane had a standby attitude indicator. Another issue to consider is the pilot's overall experience relating to instrument currency: A busy company president operating his company's high performance single engine airplane may not have had sufficient dedication and free time to maintining his instrument flying skills, . . . with emphasis on instrument scan. :ooh:

2nd Apr 2008, 19:32
Partial panel IF is taught here in Canada, and are flight test items for commercial and IFR.

Recency on the other hand, is another story...:ooh:

3rd Apr 2008, 18:51
Many thanks for the intelligent replies, guys.

4th Apr 2008, 04:35
That appears to be a Piper Meridian. The article identifies it as a Malibu.

Dan Winterland
4th Apr 2008, 05:04
Training on standby instruments is common in many systems for the training for the IR. And for IFR certification, all authorities I know of require a second instrument from a different power source. For example, if a gyro is air vacuum powered, a second gyro instrument must be powered from a battery.

This second instrument is often a 'turn co-ordinator' which is an instrument developed in America in the era of competirion between manufacturers. It is not only sensiteive to yaw, but roll as well. It may be useful for smooth flying, but it's worse for standby instruments flying than the more traditional turn and slip indicator. This is because the gyro rotates in a different direction and if g is applied, the indication is for less yaw, whereas the T and S indicates more yaw. If you're trying to recover to wings level, it's easier to unload g to get the instrument to read correctly - the T and S is better in this case. One training school I instructed at had the turn co-ordinators repalced by T and Ss for this reason.

As mentioned, training is one thing, but trying it for real in bad weather years after your training is another.

4th Apr 2008, 14:51
Most modern synthetic trainers (and PC flight simulators) have the facility for failing various flight instruments including the ADI and HSI. This ensures valuable practice at limited panel simulation is readily availble to those pilots keen enough to practice. Much depends on the motivation of the pilot, of course. Some are deterred by the difficulty of limited panel practice since it really sorts the men from the boys. But to be proficient you have to keep up regular (weekly) practice on limited panel in a simulator or synthetic trainer.

Saw one businessman who owned a Cirrus practicing ILS after ILS in an Elite model synthetic trainer. He scorned limited panel practice saying it would never happen in his Cirrus. During a holding pattern in the synthetic trainer he was unaware the ADI was "frozen" by the instructor and within 45 seconds he was in ye olde graveyard spiral. He stormed out of the room and took his business to another flying school...

5th Apr 2008, 02:37
AvCanada (http://www.avcanada.ca/forums2/viewtopic.php?f=54&t=41310&start=50) shows a picture of the panel.

As well as the pilot's AH, there is a copilot's AH plus two turn coordinators. One would like to think that among fourinstruments you could use to keep the wings level, you would be able to figure out the one that went wrong and follow the other three.

Of course it could also be a vacuum failure and possibly both DGs and AHs were dependent on a single vacuum source, but I would like to think something like a Malibu Juetprop would have redundant vacuum sources.

5th Apr 2008, 03:08
Piper Meridian Turboprop. Malibu is Piston powered. May I be the first to suggest that though tragic, it needs to be addressed the sophistication of the Aircraft and my (admittedly presumptious) suggestion that a professional Pilot (corporate) may have done things differently. I have no way of knowing the skill level of FP in question, but my assumption is that a full time CEO may not have time to become and remain current in such a comprehensive aircraft. Thurman Munson purchased a Citation as a Yankee Catcher, and crashed with a friend aboard, as well as his FI in RHS. The Doctor Bonanza paradigm comes to mind. There seems to be a high level of consternation here regarding how the incident unfolded, but Pilot skill level could have alot to do with the accident.

Dan Winterland
6th Apr 2008, 04:44
A question for those who fly single engine IFR.

A vacuum powered AH will fail if the engine stops. If your licence and ratings allow you to fly in cloud, have you ever trained for - or even thought about this scenario? When teaching people for the UK CAA IMC rating, I used to concentrate on this emergency. It's a life saver.

6th Apr 2008, 05:26
can fail with the engine running just fine. Alt. vacuum is a must in IMC, but again, this is a Turboprop. Too many fallback dials remained, (according to the story) for someone to drop from 27K to 20K, shed wings and tailfeathers, and ....... I thought the Malibu/Meridian airframe had been cured of high altitude wing shedding. As of today (to my knowledge), more airframe failure fatalies with this type than panel loss induced over-stress. High aspect wing, long moment/arm, G-sensitive. I think more to follow. And what was that "obviously not pilot error" crack?

6th Apr 2008, 06:34
The Piper Meridian and Mirage are actually NOT the same aircraft, if you see them side by side....just a minor point. Both have glass cockpits and alternatively powered stand-by instruments. The airframes, after the incidents mentioned from years ago, were thoroughly tested, and guess what? They far exceed the construction requirements for the aircraft. There is still a pilot in the front end and he still has to load it properly, fly it properly and if he/she does not, it will bite back! On every aircraft I have flown, in any case. Jealous wenches, they want your attention!

So I tend to agree that CEOs piloting themselves about, are like doctors who treat themselves....they have fools for patients!!

About 400 hours in Mirages, and the same in Meridians..... Flown them all over the world and they handle ice preety well. Prefer the PT6, I must say!

6th Apr 2008, 11:45
Is a challenge for any Piper Malibu, Mirage, or Meridian Pilot. They are short-coupled and hence easier to spin and more difficult to recover. A function of the high aspect ratio wing, a quirk to be aware of if one starts to get away from you. But you are absolutely correct, it is a quality airplane; a friend owns one. Damnably expensive, a good looking and capable investment.

7th Apr 2008, 00:54
"but can any acro be accomplished partial panel"

The exercise was directed at the UA recovery training value and was part of a basic IF training program including most flights blind from engine start to stop. I can't really say how "good" (or "bad") the aeros were on limited panel (not having any external view) but the instructor seemed happy enough with the external views. I was aware of where I was throughout, quite comfortable with the sequences .. and had no great difficulty ending up in the desired flight path at the end of each manoeuvre sequence. Certainly, at the end of the training sequence, I had a very good idea of where the aircraft was with this or that panel presentation .. which was the principal goal.

7th Apr 2008, 15:43
Limited panel can be a significant challenge in adverse conditions for many pilots. I recall the tragic accident of an Embraer Bandeirante at Leeds Bradford in 1995.