Mooney down in Atlantic

[fantom]

Some react negatively to speculation about accidents like this, but I believe it's both a good learning exercise and one legacy from the unfortunate pilot to all of us. That these sad losses force us to THINK about how we fly is good, and my belief is that the departed aviator wants us to learn from whatever happened.  

Discussion with other pilots forces us to analyze what happened, question possible procedures, think about what we might do in similar circumstances, review alternative scenarios, remember what a dangerous avocation GA is, all resulting in healthy introspection...usually not a pilot strong point. 

Just look at all the wisdom already posted here. 

Edited September 11, 2015 by fantom

[N601RX]

If the engine quite at 25,000 why would the autopilot decend from 25000 down to 12000 relatively smoothly with only minor ground speed loss (likely due to ktas or wind changes) and then suddenly cut the airspeed in half and stall the plane.  Some other event had to have happened at 1200.  Will this autopilot disengage in turbulence?  

Edited September 12, 2015 by N601RX

[Marauder]

If the engine quite at 25,000 why would the autopilot decend from 25000 down to 12000 relatively smoothly with only minor ground speed loss (likely due to ktas or wind changes) and then suddenly cut the airspeed in half and stall the plane.  Some other event had to have happened at 1200.  Will this autopilot disengage in turbulence?  

I watched a video on the Cirrus version of the Garmin AP. It has acknowledgement features built in. If you don't respond, the plane begins a descent to lower altitudes. Not sure the Mooney version has all of these features. It would be nice if someone who flies an Acclaim could chime in on the capabilities of the AP.

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[Shadrach]

I don't think the ailerons have much to do with ALT hold?

Clarence

edited...Duh!

[Piloto]

If the engine quite at 25,000 why would the autopilot decend from 25000 down to 12000 relatively smoothly with only minor ground speed loss (likely due to ktas or wind changes) and then suddenly cut the airspeed in half and stall the plane.  Some other event had to have happened at 1200.  Will this autopilot disengage in turbulence?  

If the autopilot was left on altitude hold it will try to hold altitude by pitching up with no engine power, this would explain the slow down in airspeed and descent. The plane keeps pitching up and slowing down until it stalls at 73kts ground speed with flaps up and goes down at a high descent rate.

José

[Deb]

This is a terrible tragedy and our hearts go out to Dr. Moir's family.

We do not wish to speculate on the cause of this accident. With regards to the behavior of the G1000 and GFC 700, if it is following a flight plan in GPS navigation and altitude hold mode, the airplane would continue to maintain its track after passing the last waypoint in the flight plan. As Mike said, an acknowledgment is required for a descent to be initiated on a vertical navigation (VNV) flight plan. As others have posted, in the absence of any input the autopilot will attempt to maintain the selected altitude with increasing trim. There is no envelope protection as in the Garmin Perspective system in the later Cirrus aircraft. (Vertical Speed mode and Flight Level Change mode as well as Pitch mode have ranges.)

[yvesg]

If the engine quite at 25,000 why would the autopilot decend from 25000 down to 12000 relatively smoothly with only minor ground speed loss (likely due to ktas or wind changes) and then suddenly cut the airspeed in half and stall the plane.  Some other event had to have happened at 1200.  Will this autopilot disengage in turbulence?  

Perhaps the pilot re-gained conciousness when reaching 12000, disengaged the autopilot but could not re-gain control of the aircraft due to weather? It would be difficult to be able to realize after waking-up that you have to switch the tank to get the engine to restart etc.

Yves

[gsengle]

My guess is that the altitude hold kept full up trim which resulted in the 1500fpm 140kt average speed descent, but that as the aircraft oscillated between near stall and dropping the nose, it finally dropped a wing and spun down. My question is how a long body behaves full up trim, clean, in a glide...

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[N601RX]

According to charts, the water in this area is shallow. I googled the g1000 and it appears that provided data logging is turned on and the software version supports logging it saves very detailed data once a second.  In addition to all the engine parameters, it also saves pitch, roll, altitude, vertical airspeed and indicated airspeed among others.  Hopefully this data can be located and should lead to an accurated finding of what happened.  

[M20F-1968]

I watched the weather since Monday as I was planning to go to this seminar.  Wed. ATC thought that the front would move through and the weather would improve late Thursday going into Fri morning.  By Thursday morning it was clear that the front had become more stationary with convective sigmets all along the coast from Boston to Atlantic City.  At that point it was a no go by all measures.  I would have liked the seminar to have been cancelled, rescheduled, or at least delayed a day or prolonged.  That would have removed the temptation to go despite the conditions.   I made the decision not to go Thursday morning.

As a physician, I know of the time pressures involved to be in a certain place at a certain time, and the pressures of adhering to a patient schedule.  When I learned to fly, I was a professional musician thinking about medical school.  My flight instructor told me that I was entering a profession that had the highest rate of accidents.  I think the pressures of practicing medicine are part of that statistic that all of us in medicine (as other professions) have to be aware of and respect.  Remember the risk reward equation every time you think you need to be somewhere.  

This is a tragic loss and my prayers go to the family and all involved.

John Breda

[cliffy]

I'm with donK, this has all the earmarks of an O2 problem. 

Also, (and I'm not second guessing the pilot) I wouldn't have gone. That weather would have me concerned if I was still in a Boeing. 

I don't know what the cloud tops were but I'll bet higher than 25,000'. One thing I learned in over 50 yrs of flying- you can't out climb a T storm no matter what your in (civilian mode). I've seen cells I couldn't out climb in a light 757. They grow way too fast. 

I also believe that if you're going into Class A airspace you MUST have a trip in an altitude chamber. I did many years ago and it taught me a lot about how my body reacts to hypoxia. An O2 meter and backup O2 bottle are mandatory for anything over 17,000' in my mind. Up high in a non-pressurized airframe everything is secondary to O2 flow, period! Hypoxia kills from jet drivers down to us lowly SE tin can drivers. 

My condolences to the family. I've seen it up close too many times in this business and it always hurts. 

[WardHolbrook]

I took a look at his past flights on FlightAware and on the longer ones he sure liked to fly his Acclaim at FL250. There is absolutely nothing wrong with that, but one needs to realize that you must be solidly on your A game up there. The past few years we're seeing more and more propeller-driven singles up in the flight levels and we're also seeing, on an increasingly more frequent basis, that any malfunction, mistake or neglect can carry a huge penalty.

I'll echo what others have said about a small back-up O2 bottle to keep by your seat and pulse oxymeter.  Anyone who can afford something like an Acclaim should be able to afford a pulse oxymeter and a back up O2 bottle; however, you need more than that. I believe that altitude chamber training would be a good idea for any pilot and it ought to be mandatory for anyone operating an airplane 10,000' msl. Chamber training is easily available at little or no cost. There really is no excuse for this. That's my opinion and I'm sticking to it.

[Bravoman]

I fly with a backup O2 bottle and a pulse oximeter all the time. Still, it concerns me that if there is a failure of the primary system the effects could be quick and most importantly insidious. I am quite frankly afraid to fly much over 18k because useful consciousness falls off very rapidly north of that altitude. I plan on doing altitude chamber training to see how my body reacts at the various levels. I am sure one can be quickly overcome by hypoxia before realizing it and then have no meaningful opportunity to react. It is also my understanding that the older you get the less chance you have if something goes awry.

[carqwik]

This accident brings up an interesting question (at least for me): What might be the probable cause for an O2 system failure at FL250 versus say 15,000 feet?  Based on his previous flights, his system worked just fine so why now on his last flight did it fail?  Has anyone had an O2 system delivery failure in flight at any altitude (besides simply running out of oxygen in the tank)?  Mask issue?  Freezing issue?

The only failure in my O2 system was a leaky regulator which delivered enough O2 to me but also let some out while it was doing so...but this wasn't at FL250 so....hmmm, raises questions whether it would have leaked even more and thus would have made me hypoxic if high enough? 

[bradp]

For those who know the systems well is water contamination a possibility?   FLs and pressure differential across the regulator can lead to ice quickly.   

[Marauder]

This is a terrible tragedy and our hearts go out to Dr. Moir's family.

We do not wish to speculate on the cause of this accident. With regards to the behavior of the G1000 and GFC 700, if it is following a flight plan in GPS navigation and altitude hold mode, the airplane would continue to maintain its track after passing the last waypoint in the flight plan. As Mike said, an acknowledgment is required for a descent to be initiated on a vertical navigation (VNV) flight plan. As others have posted, in the absence of any input the autopilot will attempt to maintain the selected altitude with increasing trim. There is no envelope protection as in the Garmin Perspective system in the later Cirrus aircraft. (Vertical Speed mode and Flight Level Change mode as well as Pitch mode have ranges.)

Thanks for the explanation of the system. Based on what you wrote, if the AP stayed engaged despite the decreasing altitude, it would explain the apparent controlled initial descent and decreasing airspeed. Once the AP reached it's disconnect point, I suspect it disconnected and with full trim up, it would create a nose up situation and probably quickly, a stall. FlightAware data has gaps in it. I hope they find the plane's electronics, perhaps it could provide some additional information.

I'm reading additional news reports that say he was not talking to anyone for 2 hours. I'm surprised there were no attempts at interception, especially considering the area he was flying through.

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[DonMuncy]

Most of the O2 systems I am aware of use push-on hose connections and it is possible one could dislodge without being noticed. I have never had one come loose.

[Danb]

Don 

I actually have had hose come off a couple yrs ago, noticed the sharp decrease on my oximeter somewhere under 88. I fumbled so much trying to get the hose pushed back on to the oxisaver my wife had to slide it on for me. Quite an eye opener I believe I may have been at 16000 ft, I believe we all lose our bearings at different altitudes.

 

we were told by the tower supervisor in AC on Friday afternoon that they did scramble the F-16s..but I don't know we're or when I was still in to much shock and did not ask..

[WardHolbrook]

 

Edited September 12, 2015 by WardHolbrook

[kortopates]

This accident brings up an interesting question (at least for me): What might be the probable cause for an O2 system failure at FL250 versus say 15,000 feet?  Based on his previous flights, his system worked just fine so why now on his last flight did it fail?  Has anyone had an O2 system delivery failure in flight at any altitude (besides simply running out of oxygen in the tank)?  Mask issue?  Freezing issue?

The only failure in my O2 system was a leaky regulator which delivered enough O2 to me but also let some out while it was doing so...but this wasn't at FL250 so....hmmm, raises questions whether it would have leaked even more and thus would have made me hypoxic if high enough? 

Referring only to built-in O2 systems in our turbo Mooneys:

There are two possible kinds of leaks. High pressure leak or low pressure leak. The high pressure fill line from the filling portal to the tank is also tee'd to the cockpit gauge. There is a valve spring, like in a tire, that seals the portal and numerous connectors that seals small 1/8" copper line that is used from the portal to the gauge in the cockpit. Almost always a leak in the high pressure line will be  at the valve spring or a connector that will take days for the tank to empty. I flew with one from west coast to east coast on one full tank of air over a couple days and then back on a fresh tank with a leak in the valve spring till I could get it fixed and never had less than ~900psi (but I also stayed out of the flight levels and have a backup supply).  The key thing though is a high pressure leak is always leaking, whether O2 is on or off.

Low pressure leaks occur through the O2 regulator and almost always are limited to when the regulator is on. There is one significant exception to this and that is when your tanks get hydro'd. When being re-installed the cable operating the regulator valve has to adjusted precisely such that the regulator is entirely off when the cockpit control in turned fully to the off position. I don't consider this MILF a leak myself but it's sure going to seem just like a leak to the pilot that is unfamiliar with their 02 system and rigging adjustments and probably much more common than a truly leaking regulator. Regulators should last  the life of the composite tank.

Our regulators are a two stage regulator. The first stage brings the pressure down from ambient tank pressure to somewhere well in the 2 digit psi range. Then a second stage regulator adjusts it down further for altitude. These were originally intended to work without flowmeters, but these days given the expense of O2 and the pilots desire to make their O2 tanks last as long as possible, virtually everyone that uses their O2 system with any regularity will be using a A4 or A5 flowmeter to precisely control the flow rate of 02 for either a cannula on one scale or mask on another scale. The flowmeters are added safety too since they give you a good visual on the O2 flow rate.

The most probable causes of a malfunction is on the pilot side as Don mentions in his post. Its not likely the Scott connector we use will ever slip off once its been properly twisted on and locked in place with a positive catch. But occasionally it doesn't get pushed in properly during pre-flight and there is no flow after the cockpit control is used to turn it on. But that's obvious even before you test yourself with a pulse oximeter. You can smell the O2 and you can pretty much feel it and if you can't feel it, then you can see the ball on the flowmeter showing  the level. In the absence of a flow meter the FARs require a little device that shows the 02 is flowing (kinda like a check valve that shows when it opens for flowing O2 - I haven't used one in years because I use flowmeters). This always sorts itself out right after you turn on your O2, but someone not using a flowmeter would be more likely to miss such an issue at the start.

Once positively connected the Scott connector is really not going to disconnect on its own.  It requires it to be pushed in against pressure and then twisted. But I have been flying high a long time and personally experienced having the hose pop off the connector. For the pilot it should be obvious, since its in sight by the left armrest. For the co-pilot its not so obvious since connector is behind you in the rear left seat. When it happened, just pushing it back on was insufficient since the hose had expanded enough under the light pressure of the O2 that it would pop right off again shortly thereafter; and then quicker the next timer... I had to hold it place (or go down) to keep it attached, but it turned out to be a minor nuisance keeping a hand on it since we were VMC and had the option of going down (with some minor deviation) to lower terrain anytime. I now always carry a pair of surgical scissors accessible to me from the back seat to cut an inch of tubing off to get a fresh end and have since also bought special crimper tool that enable me to place a metal clamp on the hose at the fitting to also prevent this. (The original one that popped off the first time had the metal clamp on it too. However a fresh end of tubing held tight just fine for years before it gets loose but I always now use the metal clamps on all O2 hoses for the added security.)

For those who know the systems well is water contamination a possibility?   FLs and pressure differential across the regulator can lead to ice quickly.   

Absolutely not. It should be virtually impossible in this age to get moisture in the O2 supply. The FARs require us to fill the tank with ABO, or aviators breathing oxygen. ABO is tested and logged by the gas dispenser to meet the requirement of essentially being dry air. But in these modern times all the big gas suppliers make their 02 in a manner that is moisture free and the ABO comes from the same manifold as the welding O2 and medical O2. So most DIY pilots stop right there in their reasoning and use welding O2 tanks to fill their systems. But wait there is more. When the gas shops fill tanks used for breathing (ABO and medical O2 tanks are labelled as such) they don't just simply empty it (if they even do that) and fill it with fresh O2, they empty it and then clean the tank. They actually vacuum it multiple times to make sure its as clean as possible and then fill it. If you started the process with new tanks to get welding O2 it probably would never matter, but new tanks are unheard of. Most people that fill their own either buy them from the gas supplier as used tanks labelled for the gas they want (as I did) or find old welder o2 tanks  at swap meets or the like. Although odds are if ait ll worked out ok after the first usage, its probablhy going to be fine thereafter too.

Most of the O2 systems I am aware of use push-on hose connections and it is possible one could dislodge without being noticed. I have never had one come loose.

Nor me on its own - just the hose popping off was the closest to this.

Our 02 systems are very simple and reliable. Leaks happen but catastrophic leaks are unheard off and should never be an emergency. Still though there is no need to bet your life on it. Little tiny single use 02 cylinders are available for emergency use. I always keep 2-3 in the seat back for any such emergency, and personally I won't fly above 22-23K without them on hand.

But lets say the worst happens, for what ever scenario you want to come up, lets imagine you're find yourself out of O2 in the flight levels and you don't have any back up 02. Are you dead? Unlikely if you react immediately. Its the pilot that doesn't treat it like the emergency that it really is that will succumb from hypoxia. We've all seen those tables that show times of useful consciousness (TUC) at altitude without O2 - they show 3-6 Min at FL25. Almost double that at FL22 with 5-10 min TUC and at FL18 its 20-30min TUC. Do you think you can loose 5+K fast enough from near 25K to survive? I think most of us can. But therein lies perhaps one of the more valuable lessons from the Altitude Chamber ride. From 25K without supplemental 02, all of my peers in the class went at least 5 min and I went 8 1/2 minutes before putting the mask back on. I think most of us can make it down as long as we notice it right away and either reach for backup or descend immediately. Don't just ask for lower as one pilot we all heard about recently did and didn't survive as a result. Instead tell ATC your descending now for O2 issue and ask him for a vector to avoid traffic if you like.

But often we fly high to get above weather. Thus we may not always be in a position to be able to safely descend immediately without some amount of deviation first. This is, in my mind, one of the main reasons underlying the importance of carrying some backup O2 to give you some options when you need it or if you are having a really bad day and for some reason fail to recognize your O2 sat has plummeted and you are running out of time. A backup supply enables  you to have some 02 immediately before you are able to get lower.

Edited September 13, 2015 by kortopates

[WardHolbrook]

I don't know what happened to my original response to Bradp's question, but it didn't show up. I'll try it again...

Brad posted this: "For those who know the systems well is water contamination a possibility? ..."

I really doubt it. Back in the day there were various types of oxygen - welder's, aviators breathing, medical, etc. and if you used an oxygen with a high moisture content you could creat serious problems for yourself. Nowadays, it all comes from the same source and is drawn from the same tank. It's all the equivalent of aviators breathing oxygen and if they want to use it for medical purposes they'll run it through a bubble humidifier to get it moist enough. But as far as pilots are concerned, oxygen is oxygen.

It's unfortunate, but this tragedy appears to be simply just another hypoxia related accident. There are many pilots who don't give flying in the mid and high altitudes much thought. The FAA requires precious little when it comes to training. It's the classic "What's legal isn't always safe" scenario. It's sad, because you really need to be on top of things (Pun intended) when you're up there. If you're up there and your supplemental O2 is interrupted  - for any reason - you've got precious little time to either get it restored or to get down to a breathable altitude. (It merits declaring an emergency and beginning an immediate descent.) Meanwhile, while that clock is ticking, one of your physiological responses to the lack of O2 will likely be a heightened sense of well being - a pretty deadly response as we have seen time after time. Without supplemental O2 the "lights" will go out after a few minutes and then it's just a matter of time...

There's really no excuse for not having the proper tools - a pulse oximeter, a standby, backup O2 bottle and chamber training. The last time I checked you could get a small O2 bottle, regulator and mask for around $400. It was about the size of a small thermos and provides about 20 minutes worth of O2 for one person - just enough to get your butt down to a breathable altitude. It would easily fit in a map pocket or between the seats where it could be immediately reached in the event it became necessary. Good pulse oximeters are dirt cheap and chamber training is available free for the asking, all you have to do is get to one. 

 

  

    

[Joe Zuffoletto]

I watched a video on the Cirrus version of the Garmin AP. It has acknowledgement features built in. If you don't respond, the plane begins a descent to lower altitudes. Not sure the Mooney version has all of these features. It would be nice if someone who flies an Acclaim could chime in on the capabilities of the AP.

I researched the Cirrus G1000 setup and can say that the autopilot in the Acclaim does not have these features. Would be nice if it did.

[Bennett]

My old Mooney 261 conversion had a ceiling of 28,000'. I flew her high on most my flights across the U.S.; often at FL 270 eastbound. Hostile environment, with my feet burning from the heater, and my face "freezing" cold. I used to wear a fur lined leather jacket. Flying westbound at FL 260 (only time with mild headwinds westbound at that altitude) with a CFII friend we decided to experiment. First he took off his O2 mask, and then I observed him. He lasted about 3 minutes before he was giggling and acting strange. Took just a minute or two after he put his mask back on (I had to help him). Then it was my turn. I didn't last as long as he did. I just went sleep, I always had a potable O2 bottle already hooked up, with its own masks, in addition to the built in tank. I also used Oxsavers and the regulator that had a red ball in a tube to monitor the O2 flow, and this tube was routed to be in sight. When it came time to buy another Mooney, I chose a J model, which will never get to the flight levels. Different use for this airplane.

[gsengle]

I almost attended the AC PPP. Are attendees/instructors on this discussion? Did you learn of the crash before the classes began? Must have been somber...

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[Piloto]

 

I watched a video on the Cirrus version of the Garmin AP. It has acknowledgement features built in. If you don't respond, the plane begins a descent to lower altitudes. Not sure the Mooney version has all of these features. It would be nice if someone who flies an Acclaim could chime in on the capabilities of the AP.

 

 

 

 

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I would not feel comfortable heading south/north over the Andes with this feature. Pitching down an Acclaim without a power reduction can get you close to Vne into lower altitude turbulent air. Also no warning to ATC of a descent could lead to the possibility of a mid air collision. I don't think it would had made a difference in this incident.

José