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Skymaster Arctic Circle Ditching.
Amigos,
A 337 apparently just ditched south of the Anctic circle when both engines stopped turning. Both occupants survived, according to the BBC article at the following address: http://news.bbc.co.uk/1/hi/world/americas/7773046.stm Does anybody know what happened to cause both engines to stop? |
purely speculation, and dependent on altitude, but Brian Von Herzon has said that if the temp is below -34, fuel does not flow. There is apparently a placard on Malibu Mirages limiting operations due to temp. That is because the Mirages don't have fuel heaters. Neither do Skymasters.
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Larry,
I am not sure about that, only because I flew my P210 at FL230 at -40 ( C of F, your choice!) for 3 hours and had no problems. The P210 has no fuel heating either. I have read of dissolved water in fuel crystalizing out at very cold temps and clogging fuel systems though. That is why Cessna suggested Prist or Isopropyl Alcohol be added to the fuel if operations in very cold temps were anticipated. There were a few paragraphs about this in the P210 POH, as well as a graph showing how much Prist or Isopropyl Alcohol to add. The other Cessna P twins have oil heated fuel spiders I think. |
As i said, it's speculation.
it's been so long since I heard Brian talk about that, my memory is hazy. Maybe a brain cloud :D |
This is really ironic because I sold a dozen or so SOAPA t-shirts from the 2008 fly in to Troels Hansen. The Skymaster was in Ohio having a major avionics upgrade. Troels had told me that he was going to be flying the aircraft back to Sweden. I assumed it was his Slymaster but appearently not. Nice guy, I am really glad to hear they are alive. They are really lucky. Too bad about the aircraft though.
http://www.theglobeandmail.com/servl.../National/home http://www.avweb.com/eletter/archive...ll.html#199361 That just made my heart stop when I read his name. |
The photo is just incredible
Maybe they will be in the states next year, and will come and talk about it. |
They are two very lucky fellows. God was smiling on them that day for sure.
Daev |
I agree they were so fortunate!!! Yikes!! I can't imagine a worse place to have to land, except the freezing water with no ice. It is too bad we will never know what really stopped both engines. Good comments on a lot of sites about being prepared for this sort of situation though.
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Quote:
I am presently in Iqaluit. I only have minor injuries. I will write my story in this forum when I get home to Sweden. Thank you for all the kind words and thoughts. I sure leaned about survival from this. Regard Troels Hansen (former Skymaster owner) |
we are all thankful you are alive.
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From AOPA Online:
Arctic rescue saves ferry pilots Skymaster makes forced landing on ice floe By AOPA Publications staff A Cessna 337 Skymaster on a transatlantic ferry flight made a forced landing on an ice floe near remote Baffin Island on Dec. 7, and the two pilots survived 18 hours in sub-zero temperatures by walking. The twin-engine, centerline-thrust airplane reportedly lost power in both engines and went down on an ice floe. But the ice was less than a foot thick, and the plane broke through and sank, taking the pilots’ life raft and survival gear with it. With no food, shelter, or fuel for a fire, pilots Oliver Edwards and Troels Hansen, who both live in Sweden, paced through the night as temperatures dropped to minus 20 C and into the next day before a shrimp trawler located them Monday. A Canadian military helicopter brought them to Iqaluit, a small town on the southern tip of Baffin Island, where they were reported in good condition. “They were very healthy,” Bo Mortensen, captain of the Atlantic Enterprise, the trawler that located them, told the Canadian Globe and Mail newspaper. “One of them was frostbitten on his feet. They were smiling and crying.” The pilots wore survival suits designed for water landings. They had taken off from Labrador for what they expected to be a two-to-three-hour leg on their overwater journey to Europe. When both engines failed, they made emergency radio calls, and a Canadian rescue center in Halifax coordinated the search. The Atlantic Enterprise was about 180 miles away from the place where the airplane touched down. Both pilots escaped the sinking airplane through the side windows. D |
Considering the possible factors leading to ditching
Greetings fellow SkyMaster pilots:
Thinking about the double engine failure of the SkyMaster recently off Baffin Island, several thoughts come to mind. The sort of things that commonly cause double engine failures include: 1. fuel contamination 2. fuel system icing 3. induction air icing 4. dual-engine vapor lock 5. fuel starvation The distance from Wabush NL to Iqaluit is 652 nautical miles. According to Wunderground, surface winds were 10 knots out of the south or east, resulting in a tailwind or cross wind, not much to worry about. With 7-8 minutes to landing, they could have been at about 4500 feet when the engines stopped (the MEA for the region). The weather at Wabush was light snow and -10 to -8 celcius. Assuming dry adiabatic lapse rate of 3C per 1000 feet, at 4000 feet they would have had temperatures of -22C, not low enough to gel the fuel. Minimum temperature at Iqaluit was -17C that day, or -29C at 4000 feet, probably still not quite enough to gel the fuel. Conditions were probably warmer than that, given the high level of moisture (enough for it to snow most of the afternoon). So gelling the fuel is improbable given the temperatures. Cessna says to add 1% anhydrous isopropyl alcohol if the aircraft will spend much time at minus 30C or colder. Note that there is a lot of heat capacity in the fuel, so it takes a few hours to cold soak the fuel enough for it to gel. The light snow for several hours before departure suggests the hypothesis that ice could have accumulated on the air induction system. I have never had a problem of this sort, even when flying for over an hour in ice accumulation regions (not recommended). Also it would seem improbable that the two engines would ice over at nearly the same time, especially given the assymetric configuration. Fuel contamination would seem to be ruled out unless they had just started drawing fuel from alternate tanks, but even then you would imagine that all tanks were filled from the same source in Wabush, so the main tanks should have failed much earlier unless the contaminant was much more concentrated in the aux tanks than in the main tanks. One other possibility is that of vapor lock. In the T337G modified that I fly, it is very common to have fuel interruption in one engine as we climb through 11,000 to 13,000 feet, especially at low fuel flows. The fuel seems to vaporize in the injector lines, even more so when the fuel flow is low as the fuel has more time in the line to vaporize due to the lower flow rate. Did the pilots turn on the low pressure fuel boost when the first engine lost power? Still, these heating effects tend to be assymetric on the front and rear engine, and would not typically result in both the front and rear engines quitting within minutes of each other after 3-4 hours of operation. The best timer of this sort are the fuel tanks themselves. Pilots go to great lengths to match the fuel flows of front and rear engines. The fact that the two engines quit within minutes of each other provides a lot of useful information. Some SkyMasters have electromagnetic wiggle pumps for transferring fuel from aux to main tanks. I often have these freeze up on me in cold weather, especially if there is a bit of moisture in the fuel. Ice may accumulate in the pump itself (or water that freezes on takeoff). The net result is that it is common for these pumps to freeze within the first hour of operation (when you can't pump the fuel because the main tanks are too full). By the time the second hour rolls around, the wiggle pumps may be already frozen, resulting in dead fuel in the aux tanks. Skymasters have so many tank configurations that it can be hard to determine how much fuel these main tanks had. However, based on where the engines quit, they were airborne for approximately 3 hours and 42 minutes. We should probably hear from the pilots themselves about their fuel management approach and what they observed. Given that pilots tend to actively manage their fuel flows to keep them nearly equal, and given the short amount of time between the first and the second engine quitting, and given that fuel contamination, dual-engine vapor lock, fuel icing and induction icing seem improbable (and produce different symptoms), we should consider the possibility of fuel starvation more carefully. Such fuel starvation could of course be caused by the inability to transfer fuel from one tank to another. The pilots may be able to tell us in detail what fuel management they used, what tanks were available, and what the state of their fuel was on takeoff. From that information we might be able to learn more about the nature of the problems they encountered. By the way, one thing I learned from reading about this experience was the essential need for good waterproof lighting around your neck (to signal the helicopter!). The best one I have found is a green laser flare from Greatland Laser. 30 mile range signaling to an aircraft at night! I am just blown away that you can actually see this pen laser from 30 miles away with the naked eye, but I believe it! Equipped has a good article: http://www.equipped.org/rescuelaser.htm https://www.greatlandlaser.com/index.php?productID=162 I haven't tried it yet and have no affiliation with the company. Weather at Wabush NL(departure) the day of the ditching: 10:53 AM 14.0 °F / -10.0 °C 10.4 °F / -12.0 °C 86% 29.75 in / 1007.3 hPa 1.5 miles / 2.4 kilometers ESE 6.9 mph / 11.1 km/h / 3.1 m/s - N/A Snow Light Snow 11:00 AM 14.0 °F / -10.0 °C 10.4 °F / -12.0 °C 86% 29.86 in / 1011.1 hPa 1.4 miles / 2.2 kilometers ESE 6.9 mph / 11.1 km/h / 3.1 m/s - N/A Snow Light Snow 12:00 PM 15.8 °F / -9.0 °C 12.2 °F / -11.0 °C 86% 29.84 in / 1010.3 hPa 2.0 miles / 3.2 kilometers SE 8.1 mph / 13.0 km/h / 3.6 m/s - N/A Overcast 12:05 PM 15.8 °F / -9.0 °C 12.2 °F / -11.0 °C 86% 29.72 in / 1006.3 hPa 2.0 miles / 3.2 kilometers ESE 6.9 mph / 11.1 km/h / 3.1 m/s - N/A Snow Light Snow 1:00 PM 15.8 °F / -9.0 °C 12.2 °F / -11.0 °C 86% 29.81 in / 1009.4 hPa 1.2 miles / 2.0 kilometers ESE 9.2 mph / 14.8 km/h / 4.1 m/s - N/A Snow Light Snow 2:00 PM 15.8 °F / -9.0 °C 12.2 °F / -11.0 °C 86% 29.79 in / 1008.6 hPa 1.1 miles / 1.8 kilometers ESE 9.2 mph / 14.8 km/h / 4.1 m/s - N/A Snow Light Snow 3:00 PM 17.6 °F / -8.0 °C 14.0 °F / -10.0 °C 86% 29.77 in / 1008.0 hPa 2.1 miles / 3.4 kilometers ESE 10.4 mph / 16.7 km/h / 4.6 m/s - N/A Snow Light Snow 4:00 PM 17.6 °F / -8.0 °C 14.0 °F / -10.0 °C 86% 29.76 in / 1007.8 hPa 0.6 miles / 1.0 kilometers ESE 10.4 mph / 16.7 km/h / 4.6 m/s - N/A Snow Light Snow 4:19 PM 17.6 °F / -8.0 °C 14.0 °F / -10.0 °C 86% 29.65 in / 1003.9 hPa 3.0 miles / 4.8 kilometers ESE 10.4 mph / 16.7 km/h / 4.6 m/s - N/A Snow Light Snow |
Brian - thanks for the work. Interesting to me in that Im not used to flying in such cold weather and have wondered what could happen in bitter cold weather. Encounter low temps over Rocky mts occasionally but its usually bone dry and not up there all that long. Also interesting to read the AOPA post that they exited the side windows. Side window exit has been my plan for a long time cause its pretty clear that a bunch of people and stuff just arnt going out the one door very fast - glad to hear it works.
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For those relatively new to this forum, Brian von Herzen has been a member for many years, has crossed the Atlantic in his Skymaster via the northern route many times, and we were fortunate to have him speak of his crossings at the 2004 Skymaster Meeting and Fly-in held in Oklahoma City. An annotated group picture of that meeting may be found below, which allows you to put faces to names.
Ernie |
Cold Air, side windows, ditching procedure modifications
John, I have actually encountered -32C in California of all places in the spring! It was just a cold day with a norther jet stream coming straight down from Alaska! I was only up there for 45 minutes so did not worry about cold-soaking the fuel, but 2-3 hours in that weather would be enough to increase my pucker factor and consider using isopropyl! So you could definitely encounter such cold winter temperatures in the central US at altitude.
Side window exits in unpressurized craft are a good idea. Sadly, in my P337G the only solution is to jam the clamshell door open before landing using the door handle as the jamming mechanism. Any racking of the doorframe after landing would otherwise jam the clamshell shut. While this would result in a lot more float time, the exits would be highly problematic. Ironically, it may have been the side windows that caused the skymaster to sink so quickly. (although there was some mention of window breakage on this ditching). Most planes float at the level of their wings. for a low wing, this is no problem. For a high wing, it means that most if not all of the cockpit may be underwater. We should get the story from the pilots as to where the cockpit floats. Open the windows and the water will fill the cockpit in seconds. So we are left with a real tradeoff. Windows open, you can get out but you will only have seconds to do so. Windows closed, you will have minutes to ponder a watery death, but with 1 pound per square inch covering all 300 square inches of your window, you are unlikely to get that window open with anything less than a hydraulic press. Given the importance of the life raft and the water bag, I am considering modifying my procedures to have the copilot hold the life raft in his lap before ditching, and have the waterbag in my lap before reaching the surface. Downside is that the life raft will hit the yoke and force a nose first second impact after first bounce. Upside is that the life raft will be with you when you egress, like it or not. Green laser flare around my neck is the other modification to my procedures. There are just too many ways of not being found out there to not have one! Cheers, Brian |
Flight of SE-MBT
Fellow aviators.
I am in a Hotel in Ottawa waiting for my flight to Europe. Flight of SE-MBT started in New Philadelphia on the 6 of December. We had been waiting several days for a waiver from TSA allowing us to start our flight.Just in time we got the waiver and we started a 3 hrs 20 min flight to KPYM. This was the first flight with new avionics so a lot of time was spend on trying all the new functions of the recently installed equipment. The flight went well with only a few snags on all the new electronics. I will continue my story later because my internet time is running out. Rgds Troels. |
Last Flight of SE-MBT
I am now at home and that sure feels good.
On Saturday the 6 we flew from KPYM via KBGR to CYQB. Both these legs were uneventful and without problems. We parked the aircraft overnight in Quebec City with the fuselage/window cover on and the electrical engine heaters hooked up. The next morning it was snowing and I cleared the aircraft from snow when Oliver submitted the flightplans for our two leg flight to CYFB. The aircraft started instantly and all systems were operating. We flew for 2 hrs and 30 min at 11000 feet before landing in CYWK. Refueled 172 liters and checked the aircraft for next leg. We climbed to 11000 on this last flight of SE-MBT. The weather improved and we soon enjoyed the most beautyful sunset. About 3 hrs and 40 min into the flight we went from heaven to hell. We first noticed a decrease in oil temp. on the forward.Soon followed by low oil pressure. I moved the prop lever to test the response of the propeller system. While doing that the engine failed with a loud metallic scream and smoke entered the cockpit through the heating system. Mayday call transmitted on 121.5 and a KLM aircraft responded. Decend to single engine cruising altitude initiated. The rear engine oil temp and pressure decreased just like the forward and the engine failed with a loud bang. Back on 121.5 to tell the KLM that we were now gliding all engines out. Position report transmitted as well. I will be back soon with the rest of the story. Troels. |
WOW
We are all glad you are safe, but that had to be the scariest moment in life. Whay year was/is SE-MBT?? |
Hi Larry.
It was a 1966 model. I will be back with the rest of the story soon. I also feel that I have a good idea about what went wrong and I feel this forum is full of very experienced people to discuss my theory with. Troels. |
Any work done on both engines recently? Both engines overhauled at the same time, by the same shop?
Ernie |
Hello Ernie.
The forward engine was factory new in 2000 and the rear overhauled in 1996. FWD 462 TSN REAR 900 TSO I had the props,governors and all mags overhauled at the same time the avionics was done. Troels. |
Last Flight of SE-MBT
It was some busy minutes during the glide towards the cold below. Survival suit completely prepared and life vest put on and ready. Oliver sitting with life raft and some other equipment in his lap. I attempted to restart engines but of course without success. I drained the batttery trying to start engines so instrument lights were very weak. At about 3000 feet we decided to put the plane on the water just beside the ice. It was fairly easy to see the edge of the ice in the moonlight. Close to the water I selected full flaps and we hit the water with apprx 70 MPH. The nose went under and big chunks of ice crushed both windshields and the left side window. I put my right hand on the glareshield to brace myself. The aircraft stopped very rapidly and the water was up to our chest. Within seconds the cabin was completely under water. Oliver had the door open prior to impact but was now struggling to get it open. I got out through the left side window.Once out I pulled the inflate handle on my life vest and I was on the surface instantly. The left wingtip was resting on the ice and I used the wing to push myself up onto the ice. I looked back and saw Oliver in the water trying to get up on the wing. I was extremely worryed that the ice would carry our weight because it was moving and flexing a lot. Oliver boarded the ice crawling on the left wing. We talked about if we suffered any injuries and realized that the raft and other equipment was still in the aircraft. I started to crawl on the wing but the aircraft nosed down and went under. I got back on the ice and watched my company logo on the tailfin disappear into the dark water.
Last part of story to follow. Troels. |
Wow! You guys are amazing! The fact that both of you made it out of there alive and almost unhurt is a total success story! I've been flying my Skylane to Iqaluit four times in the last three years, on two occasions going to/coming from Europe. Another crossing is planned for next year. I will take every word you wrote into serious consideration, as far as survival goes. When my wife who was with me on all of the above flights, heard your interview on CBC Radio, she cried because she knew from first hand experience how it is to fly in the Arctic and what a feel of relief it is to reach dry ground after a long water crossing.
I used to own a Skymaster myself, so our thoughts are now to find out if you are able to share with us your ideas on what went wrong with the engines. I think we all understand that you must have some concerns to share some information that could be used by various agencies; however, we all want to be able to avoid what you went through. All the best, go flying soon, Gerd |
Good post from Gmas, and the arguments for partial refueling with jet fuel sound persuasive. One point I want to make is that in a standard Skymaster, without after-market engine monitoring instruments, the EGT guage isn't very informative. If you look, you will notice that there is no scale; it says 25 deg/div, so you can use it lo lean in cruise, but it doesn't tell you actual EGT. And although you might remember where it typically is, a lower reading can easily be attributed to the lower outside temperature.
Ernie |
I put diesel fuel in a regular cars once. It only ran for about 5 mins. So I wonder how the airplane was able to fly 3+ hours on Jet A?
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We refueled in CYQB saturday late afternoon. All four tanks were refueled at that point.I dont recall the quantity but close to 200 liters. On Sunday we flew to CYWK without using fuel from the AUX tanks. The flight was 2 hrs 30 minutes. The MAIN tanks were refueled in wabush with 174 liters. I was up on a latter and checked that the AUX tanks were full. This means that if they refueled the MAINS with jet fuel the mixture in the mains would be about 50/50. About 1 hour 30 minutes into our last flight I selected AUX tanks on both engines simultaneously and flew for 1 hour before selecting back to MAINS. I noticed a slightly lower EGT on this last leg than on the previous legs. All magnetos were overhauled during the time the aircraft was in the shop for avionic work. I never heard any misfiring and the mag checks were always good. Starting performance was also very good both hot and cold engine.
Troels |
The classic JetA mis-fueling scenario is: take-off, and then the engine(s) quit at about 200 feet AGL.
Is it possible to run 1.5 hours on one set of tanks, then 1 hour on another set of tanks, and then after all that time have a mis-fueling engine failure? |
Today the Canadian NTSB send me a copy of my fuel slip from Wabush. It stated that I uplifted 174 liters of 100LL.
I want to finish my story so here it comes. Standing on the 10 times 5 meter big piece of ice we started our 18 hour struggle to survive. Time is hard to tell when you dont have a clock but about 1-2 hours later the first aircraft appeared and we got our hopes up that we would be found very soon. We were not able to show ourself in any way since we did not get this equipment with us from the aircraft. Most unfortunately the small lights on our life vests did not work. Several other aircraft and helicopters searched for us during the night and they were very close about three times. I blamed myself that I did not have any signalling equipment. I think they called of the search when the ceiling got too low. I dont know how to describe it but it is extremely cold and the wind is blowing the cold air right through your bones. We worked hard for a long time to fight the cold and finally the daylight came.Now they will come back and find us we told ourselves,but nothing happened. We saw the shoreline in the distance and decided to jump from one peice of ice to the other in order to reach dry land. After doing this for about 1 hour a light flashed in the horizon. We stared in that direction for a long time wondering what that couldt have been.We continued our walk on the ice for some time but then the light appeared again,and a little closer. We realized that the light must come from a ship so we turned around on the ice and walked towards the ship waving our life vests over our heads.Suddenly the light was pointed directly at us and after a while we heard the signal horn from the ship. WE ARE BEING RESCUED. The feeling of relief is hard to describe. I am trying to figure out what happened to my engines and I have a few ideas. I want to share my ideas with you folks in this forum but it is getting late now so I will be back tomorrow. |
Climbing onto the ice from the water.
By the way, I spoke this week with my sailing friend in New England who does a lot of work in freezing salt water, and he said that it is _very_ fortunate that the wing was lying on the ice. Without the wing on the ice, it could have been nearly impossible to get up on the ice from the water even in a survival suit. Congratulations to the pilot at managing to keep the wing on the ice through the ditching process!
Best regards, Brian |
Quote:
This is not a misfueling case. |
outside air temperature
Dear Troels:
Thank you for your description of the flight. I was wondering if you read the outside air temperature at 11,000 feet during the cruise portion of the flight. The absolute minimum I would calculate would be -10C at Wabush minus 3C per 1000 ft = -43C assuming dry adiabatic lapse rate. Given the moisture at the departure, the actual ambient temperature could have been higher, perhaps between -28C and -43C at 11,000 ft altitude. Did you see any variations in fuel flow before failure? Regards, Brian |
Patricia Bell, of CBC News sent me a link to a story she did on this. It includes an audio of Troels speaking to Patricia.
Of note, there are comments by two different crews who spoke to them when they declared their Mayday. http://www.cbc.ca/canada/north/story...-survivor.html The comments are located here, and linked to in the above story http://www.cbc.ca/news/yourbeststuff...ayday_rep.html |
The indicated OAT at 11000 feet was -31 C. I did not see anu variation in fuel flow. The engine never misfired or vibrated up until the point of failure.
Troels. |
The way I see it we must have lost the engine oil. The decreasing oil temperature followed by loss of oil pressure means no more oil to me. I know that the breather lines from the outlet to the rear baffle was not insulated. I still have pictures showing that. Maybe the breather line was blocked due to the low outside temperature and the oil pumped out somewhere because of that. I was not aware that it is a good idea to insulate the breather line. I have previously owned two Aztecs and the breather line on a Lycoming are behind the baffle on the rear part of the engine. This is pure speculation but maybe some of you have some experience on the subject.
Troels. |
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Advisory Circular AC 91-13C covers cold weather operation of aircraft.
Section 4, d. says the Oil Breather requires special consideration. Frozen breather lines can create numerous problems. My Skymaster had baffles that attached inside the front engine cowling, to reduce the amount of air flowing over the engine, during cold weather operations. Unfortunately, I don't have access to the POH anymore, but I seem to think these were for operations below 20 degrees F. The whole AC is interesting reading for those who operate in cold weather. |
I've seen an aircraft that the breather line froze over, the crankcase pressure built up, and blew the crankshaft seal out, then the mess began.
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Is insulation enough?
So is all that is required to have some insulation over the line to prevent this problem?
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The oil breather line should have a knoch cut into it about an inch or two above the end to counter a frozen line. If the engines were recently overhauled perhaps the shop replaced that line but didn't read the maintenance manual about ensuring that knock was there. That knoch is why most Skymaster belly's are dirty. It's a necessary evil.
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What about the rear engine??
My memory is that the rear vapor line goes up and out the rear of the cowling, adjacent to the prop. Would that line also get frozen up?? |
What was the time lapse between engine failures???
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