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Since the untimely death of our friend (and chief charter pilot at the
local FBO) while ferrying a Spencer Air Car back from Seattle, WA last week, our local pilot community has been roiled with speculation about the cause of the crash. Of course we won't know anything definitive for a long while, but the facts we can discern are as follows: - The plane was a Spencer Air Car, a homebuilt flying boat that looks like a Republic SeaBee made out of wood. - The landing gear was down when they crashed - Witnesses say the engine sputtered, then failed. - Witnesses say they hit very hard, and "bounced like a rubber ball" before hitting again and exploding into a million pieces. - There was no fire. - The wreckage was hardly recognizable as an aircraft, evidence of how hard they hit. - The area they landed in could not be better for an off-airport landing: Flat, frozen, open Iowa farmland. - The pilot was a CFII who flew daily, in everything from a Pietenpol (he learned to fly in one, with his dad), to a CitationJet. This was NOT an inexperienced pilot. Speculation about the way an amphib like this would fly after an engine failure (with the dead engine way up high above the fuselage) seems to indicate that it could make the elevator forces much lighter than with power on, and could lead to an inadvertent stall by over- flaring. In the absence of a mechanical failure, this would seem to explain the eye-witnesses account of the crash. We're all devastated by the loss of someone who could arguably be described as our best local pilot, and I'm trying to understand the (very unusual) type of homebuilt aircraft they were flying. Does anyone here own one? Or, has anyone ever flown one? Comments on the flight characteristics would be appreciated. Thanks, -- Jay Honeck Iowa City, IA Pathfinder N56993 www.AlexisParkInn.com "Your Aviation Destination" |
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Go here to learn more about the air car including a picture.
http://www.pilotfriend.com/experimental/acft6/37.htm |
#3
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Was there a covering of snow where they crashed? Was it a bright sunny day?
"Jay Honeck" wrote in message ups.com... : Since the untimely death of our friend (and chief charter pilot at the : local FBO) while ferrying a Spencer Air Car back from Seattle, WA last : week, our local pilot community has been roiled with speculation about : the cause of the crash. : : |
#4
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Was there a covering of snow where they crashed? Was it a bright sunny day?
Yep. Why? -- Jay Honeck Iowa City, IA Pathfinder N56993 www.AlexisParkInn.com "Your Aviation Destination |
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On 10 Feb 2007 17:45:58 -0800, "Jay Honeck" wrote:
Was there a covering of snow where they crashed? Was it a bright sunny day? Yep. I suspect the OP is suggesting depth perception issues... smooth white covering, little contrast, bright sun to reduce the irises and make it even tougher to make out detail to judge height with. I flew a month ago on a sunny day right after a snowfall...and they don't plow the GA runways in this neck o' the woods. Had about 4" on the ground, and the tracks from my own takeoff were the only feature I could lock on to. If I'd had unbroken snow and an unfamiliar field, it would have been interesting. (And since the runway had been indistinguishable from the grass due to the even coat of snow, the tracks from the takeoff wiggled a bit....) The accident airplane had been based at my field, I'd seen it several times. Its hangar was right down the row from that of a friend of mine. Ron Wanttaja |
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The accident airplane had been based at my field, I'd seen it several times.
Its hangar was right down the row from that of a friend of mine. Thanks for the info, Ron. A fellow pilot who initially went to the accident scene reported that the first impact zone had ruts 8 to 10 inches deep in the (frozen solid, at 10 below zero) field where the landing gear hit. Anything that could punch a hole that deep in frozen Iowa farmland was coming down extremely fast. You can't dig the ground here with a bulldozer right now, it's frozen so hard. The next impact was hundreds of feet down the field. None of this makes any sense, of course. What could cause an aircraft to come down so hard, so fast, but still with that much flying speed? With that kind of energy, they could easily have flown on quite a ways, and the terrain was not an issue. This has been a tough one to take. We all like to believe that fatal accidents only happen to bad pilots, but in this case the pilot was arguably our *best* pilot. Understanding and studying what happened in this bizarre crash will go a long ways toward improving flight safety, IMHO, simply because it proves that it can happen to any of us. -- Jay Honeck Iowa City, IA Pathfinder N56993 www.AlexisParkInn.com "Your Aviation Destination" |
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("Jay Honeck" wrote)
None of this makes any sense, of course. What could cause an aircraft to come down so hard, so fast, but still with that much flying speed? With that kind of energy, they could easily have flown on quite a ways, and the terrain was not an issue. Were there any radio calls heard? CO poisoning? Montblack |
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Depth perception on final above the bright snow, may have misjudged altitude before the flair. Just like trying to land
on a glass smooth lake in an amphib - you basically fly a rate of descent until contact... "Jay Honeck" wrote in message ups.com... : Was there a covering of snow where they crashed? Was it a bright sunny day? : : Yep. : : Why? : -- : Jay Honeck : Iowa City, IA : Pathfinder N56993 : www.AlexisParkInn.com : "Your Aviation Destination : |
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I'll pipe up a little bit, although ultimately I think speculation,
including my own, mostly just fuels rumors and we probably are best served by waiting for the ntsb to do their job. I have been building a Spencer Aircar for the last 9+ years, it is close to flying and will likely fly this spring. I usually have a homepage up but I have removed it temporarily as people were contacting me thinking that I was the owner of the Aircar rights, owner of the kit company, etc. To be clear this aircraft is plans built, I am a builder but otherwise not a purveyor. I have not personally flown one myself, although I have had several lengthy conversations with a couple of gentlemen who have flown them extensively. Most of the active flying Aircars are flying in Florida, although there is one currently buzzing around Canada and one flying is San Diego. As far as flying characteristics, the aircar is not known for any particular bad habits when properly loaded. The engine is a pusher mount but it is not on a pylon. It is mounted behind and only about 12" above the center of lift, and also behind and approximately 24" above the CG. However, the engines thrust is directed down onto the top of a Stabilator - yes a flying tail. When the thrust is increased it is designed to be directed at the top of the tail, counteracting the thrust induced downward pitching moment. Because the aircraft is designed for water operations the stabilator has a lot of authority. It is set for 15 degrees of up travel and 6 degrees of down travel. The large amount of up travel is to provide the authority to get the aircraft off of the water effectively. The aircraft is high drag, it does not glide well. Some V numbers: Vs 53 mph Vso 43 mph (its a seaplane) Vx 62 mph Vy 70 mph Vfe 100 mph Va 140 mph Vd 180 mph The hull is very stoutly built with truss type bulkheads every 10-11". The keel + keelson alone are 1 1/2" wide by 3" tall and has a 1/4" metal strip on the bottom, mine is stainless, some people use aluminum. Basically a truss structure boat is built, and then boxed using 1/4" and 3/8" plywood, bonded to all sides and the top with what becomes the floor of the cabin, in addition it is covered with a 8 oz layer of fiberglass. The construction is strong, people have intentionally landed these aircraft in snow with the gear up, the hull acting as a sled. Several have also landed gear up on runways with no damage. The floor of cabin to keel is about 22" I would think that the nature of this construction would actually act a "crush zone" in the event of an accident. Hearing the description of the event, they must have hit pretty hard. Two critical things to mention that caught my attention. Primarily, The fuel system consists of a main tank, of welded aluminum, with a capacity of 46 gallons, and auxiliary tanks in each float with a capacity of 25 gallons each. At the time of sale the aux tanks were said to be disconnected, this from one of the prospective buyers, I have no way on knowing if this was true. Most of these tanks were built by Spence in the 70s and the fiberglass construction was not of the quality that kit aircraft see today. In general they were constructed using polyester resin and a lot of glass matt due to the complexity of the shape. If the tanks saw a lot of time in the sun they could have been in less than serviceable shape. Do the math: using the main tank only, and a conservative fuel burn, the aircraft would have run out of fuel short of KIOW. Perhaps they were planning on using the aux tanks, perhaps they didn't know they were not connected, perhaps they were connected and the lines froze, its all speculation. But it is my belief that if they were only operating on the main tank that they would have been in trouble. The second issue is that this aircraft tends towards an aft CG. In fact, empty the aircraft is at the aft CG limit. The fuel sits close to the CG, pilots in front. There are usually two batteries and anchor in the nose of the aircraft. The aircraft needs to be loaded carefully and is generally test flown with extra weight in the front of the aircraft. Again speculation, but if improperly loaded it may have been difficult to recover from an aft cg stall. This may have been compounded with light stick forces from a balanced stabilator and aft CG. The design has been around, in some form since before WWII. Spence was an artist draftsman, quite prolithic, and was piloting aircraft into his 90s. He was a test pilot for Republic. His documentation of the Aircar flight characteristics was thorough. The Aircar design was awarded the NASAD seal of quality in the 70s. To receive the "Seal of Quality" from NASAD the Aircar was required to meet quality standards as formulated by NASAD. These standards include: General Specifications. Plans and drawings standards with complete details on all Systems. Manual standards. History of experience supported by complete test records. Complete analysis by professional aeronautical engineers as to construction, engineering, and materials. NASAD is an independent, non-profit organization of aircraft designers who are dedicated to the development and improvement of aircraft and related components. NASAD works closely with the aviation and ultralight industry, EAA, AOPA, and the FAA to formulate high quality aircraft standards. While I certainly carry a bias in favor of the aircraft. I have no idea how well constructed the accident aircraft was. It did have over 2500 hours of flight time so it had some time on it. The journey was halted in Idaho as they waited for a fuel pump and alternator. This from the purchaser, who incidentally was the father of Joshua Reynolds the second victim. I understand that your local community is in mourning and shock and looking for some tangible answers in this tragedy. I hope that the NTSB can provide those answers. I do know from personal experience that even very good pilots can have a bad day. Two on our field have perished in the last twenty years, both excellent pilots. I think if anything, it should remind us that aviation is a activity that doesn't easily forgive being tired, in a rush, on medication, not physically fit, essentially not being at our peak. Imagine yourself tired, wanting to get home, cold, (did the heat work? the engine is way back there, remember the old VW bus in winter), in an unfamiliar aircraft with an unusual set of flying characteristics, not a forgiving environment. I hope this helps is some manner, My condolences to anyone who has been affected by this tragedy. Doug Palmer "Jay Honeck" wrote in message ups.com... Since the untimely death of our friend (and chief charter pilot at the local FBO) while ferrying a Spencer Air Car back from Seattle, WA last week, our local pilot community has been roiled with speculation about the cause of the crash. Of course we won't know anything definitive for a long while, but the facts we can discern are as follows: - The plane was a Spencer Air Car, a homebuilt flying boat that looks like a Republic SeaBee made out of wood. - The landing gear was down when they crashed - Witnesses say the engine sputtered, then failed. - Witnesses say they hit very hard, and "bounced like a rubber ball" before hitting again and exploding into a million pieces. - There was no fire. - The wreckage was hardly recognizable as an aircraft, evidence of how hard they hit. - The area they landed in could not be better for an off-airport landing: Flat, frozen, open Iowa farmland. - The pilot was a CFII who flew daily, in everything from a Pietenpol (he learned to fly in one, with his dad), to a CitationJet. This was NOT an inexperienced pilot. Speculation about the way an amphib like this would fly after an engine failure (with the dead engine way up high above the fuselage) seems to indicate that it could make the elevator forces much lighter than with power on, and could lead to an inadvertent stall by over- flaring. In the absence of a mechanical failure, this would seem to explain the eye-witnesses account of the crash. We're all devastated by the loss of someone who could arguably be described as our best local pilot, and I'm trying to understand the (very unusual) type of homebuilt aircraft they were flying. Does anyone here own one? Or, has anyone ever flown one? Comments on the flight characteristics would be appreciated. Thanks, -- Jay Honeck Iowa City, IA Pathfinder N56993 www.AlexisParkInn.com "Your Aviation Destination" |
#10
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("Doug Palmer" wrote)
I'll pipe up a little bit, although ultimately I think speculation, including my own, mostly just fuels rumors and we probably are best served by waiting for the ntsb to do their job. I have been building a Spencer Aircar for the last 9+ years, it is close to flying and will likely fly this spring. Thank you for that write up. Montblack |
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