Seaplane down off Miami Beach
Rigpiggy:
The picture you posted is for the original piston engine Mallard, not the Frakes turbine conversion Mallard that Chalks flys.
The picture you posted is for the original piston engine Mallard, not the Frakes turbine conversion Mallard that Chalks flys.
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With regards the fuel feed system;
- Main Tanks to Engine....crossfeed available,, the aux if fitted and the float fuel will have to be pumped into the mains on the respective side to be of any use
The flying boat in this scenario was not fitted with FDR and ironically the CVR is reported to have not recorded anything.
Latest NTSB reports say cracks were found in the spar at the root of the wing!! Goodness,, seems like the cracks were so internal and critical to find that it probably would've needed dye tests to reveal them (once again, NTSB comments!!)
Anyone with more technical knowledge/information on these sort of spar inspections....?!?! especially for the one's that operate on the salt water for over 20k hrs ?! cycles may be around 1 per hour.
A Very Sad situation in the aviation History of flying boats in particular....
Smoothie....
- Main Tanks to Engine....crossfeed available,, the aux if fitted and the float fuel will have to be pumped into the mains on the respective side to be of any use
The flying boat in this scenario was not fitted with FDR and ironically the CVR is reported to have not recorded anything.
Latest NTSB reports say cracks were found in the spar at the root of the wing!! Goodness,, seems like the cracks were so internal and critical to find that it probably would've needed dye tests to reveal them (once again, NTSB comments!!)
Anyone with more technical knowledge/information on these sort of spar inspections....?!?! especially for the one's that operate on the salt water for over 20k hrs ?! cycles may be around 1 per hour.
A Very Sad situation in the aviation History of flying boats in particular....
Smoothie....
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Ok
NOW we know the mallard had the plumbing to crossfeed fuel it can easily be understood that these lines may have broken and allowed the fuel to go "vapor" and ignite...either electrical bits or the hot bits of the engine(which seems quite intact as is the prop on the right side)
I will say I think that the wing came off and THEN all the fuel on the right side caught fire.
I will say that I think that some time ago some odd sort of stress happened which grew over time to the disaster we have seen. Could sal water corrosion be a part? sure. But maybe not.
HOW many on the forum remember the DC10 at chicago that went down in the late 70's because a crack in the mount was made by using an unapproved maintenance procedure in swapping engines?
The DC10 was grounded for about 3 weeks and a few others were found with cracks. (other factors to be sure in this crash)
Metal Fatigue is not new, stress cracks are a small section of metal fatigue.
I encourage you all to either read, "No Highway" by nevil shute, or see the movie called, "No Highway in the Sky" starring Jimmy Stewart. Both made PRIOR to the
COMET disasters of 1954 (age not a factor there!)
And to all you Britishers out there! You should be very proud of Mr. Nevil Shute and the work of the Royal Aircraft Establishment.
Oh, by the way, WW2 in the pacific would not have been won without Grumman Fighter planes like the Wildcat, Hellcat, BearCat, TigerCat. Neil Armstrong and Buzz
Aldrin would not have landed on the moon without the Grumman Lunar (excursion) Module.
Maybe all planes should be made with a time bomb on board. Big clock warns when it will go off to everyone getting on board.
20 year countdown and then get away from the thing!
Trouble with grumman is that this plane was too well made. 50 plus years is alot.
jon
NOW we know the mallard had the plumbing to crossfeed fuel it can easily be understood that these lines may have broken and allowed the fuel to go "vapor" and ignite...either electrical bits or the hot bits of the engine(which seems quite intact as is the prop on the right side)
I will say I think that the wing came off and THEN all the fuel on the right side caught fire.
I will say that I think that some time ago some odd sort of stress happened which grew over time to the disaster we have seen. Could sal water corrosion be a part? sure. But maybe not.
HOW many on the forum remember the DC10 at chicago that went down in the late 70's because a crack in the mount was made by using an unapproved maintenance procedure in swapping engines?
The DC10 was grounded for about 3 weeks and a few others were found with cracks. (other factors to be sure in this crash)
Metal Fatigue is not new, stress cracks are a small section of metal fatigue.
I encourage you all to either read, "No Highway" by nevil shute, or see the movie called, "No Highway in the Sky" starring Jimmy Stewart. Both made PRIOR to the
COMET disasters of 1954 (age not a factor there!)
And to all you Britishers out there! You should be very proud of Mr. Nevil Shute and the work of the Royal Aircraft Establishment.
Oh, by the way, WW2 in the pacific would not have been won without Grumman Fighter planes like the Wildcat, Hellcat, BearCat, TigerCat. Neil Armstrong and Buzz
Aldrin would not have landed on the moon without the Grumman Lunar (excursion) Module.
Maybe all planes should be made with a time bomb on board. Big clock warns when it will go off to everyone getting on board.
20 year countdown and then get away from the thing!
Trouble with grumman is that this plane was too well made. 50 plus years is alot.
jon
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Trouble with grumman is that this plane was too well made. 50 plus years is alot.
The rest is OT and/or fanciful.
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Very Sad
I used to operate these aircraft for the company and they are a thrill to fly.
Old airframes, but heavy maintenence daily.
As for the spar, Grumman mandated that the spar for the larger ALBATROSS be replaced after a number of hours, replaced with TITANIUM spar at the cost of a million plus.
Very sad day for aviation indeed, highly probable that the oldest operating airline in the US will be closed for good.
My thoughts and prayers to the crew, passengers and their families.
Let the legend live in memory
Old airframes, but heavy maintenence daily.
As for the spar, Grumman mandated that the spar for the larger ALBATROSS be replaced after a number of hours, replaced with TITANIUM spar at the cost of a million plus.
Very sad day for aviation indeed, highly probable that the oldest operating airline in the US will be closed for good.
My thoughts and prayers to the crew, passengers and their families.
Let the legend live in memory
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Just to clarify on the stated Albatross spar issue;
The military versions were HU-16's with no spar life on them.
Grumman bought back or rather acquired around 16 I think back from the market and built them to 0 time naming them the G-111's. These had a Titanium spar cap installed and another emergency door installed and was certified for Charter. All these G-111's have a service life on them. Chalks operated few of these and now they are all parked in storage awaiting to go to a new home. The lowest time one is around 30 or 40 hrs or something like that !!
There's one G-111 for sure flying around happily operated by Mirabeela Yachts. This one used to be PK-PAM in Indonesia years ago.
Most of the other Albatrosses flying around are HU-16's either under a restricted or a experimental category.
Smoothie....
The military versions were HU-16's with no spar life on them.
Grumman bought back or rather acquired around 16 I think back from the market and built them to 0 time naming them the G-111's. These had a Titanium spar cap installed and another emergency door installed and was certified for Charter. All these G-111's have a service life on them. Chalks operated few of these and now they are all parked in storage awaiting to go to a new home. The lowest time one is around 30 or 40 hrs or something like that !!
There's one G-111 for sure flying around happily operated by Mirabeela Yachts. This one used to be PK-PAM in Indonesia years ago.
Most of the other Albatrosses flying around are HU-16's either under a restricted or a experimental category.
Smoothie....
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"We've always had wings"
I keep telling myself it was sheer coincidence, random ad inserts just when I looked in. Not the work of some soulless prankster at CNN. Nor Honda tempting the gods.
I keep telling myself it was sheer coincidence, random ad inserts just when I looked in. Not the work of some soulless prankster at CNN. Nor Honda tempting the gods.
Until someone complains to Honda (Ad execs at CNN could care less), the airing of the Honda Jet ad will be paired with aviation matters (or whatever other key words trigger the insertion) including the video of that most unfortunate loss of the Mallard and her PAX and crew will continue in and out of rotation.
Once full convergence occurs (digital television , internet access and on-demand programming in one box/system) you can expect more specific ad-revenue generating insertions like this based on what you watch, when and likely even where you surf the net.
Not a pretty picture - but it's the future in the capital driven world of advertising.
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jon:
While Nevil Shute Norway was in fact an aircraft design guy (dirigibles, I believe) with an appreciation for fatigue, and likely had some anticipation that future fatigue casualties would happen, Nevil Shute the author got much undeserved credit for guessing it would happen to (specifically) the Comet.
Americans and Brits (and others) all came to appreciate the durability of the Wildcat and Hellcat from the "Grumman Iron Works". But the Bearcat never saw WWII duty, and at least two F8F's broke up during postwar aerobatic exhibitions.
And Grumman's lunar vehicles were examples of outstanding performance-to-weight engineering, with just barely enough fatigue life to last one mission (that's certainly NO criticism of Grumman, just stating what they really accomplished!)
And the DC-10 problems were not fatigue-related at all, but overstress damage during unapproved maintenance procedures.
So, precious little of your original tome really addresses the current G-73 problem.
While Nevil Shute Norway was in fact an aircraft design guy (dirigibles, I believe) with an appreciation for fatigue, and likely had some anticipation that future fatigue casualties would happen, Nevil Shute the author got much undeserved credit for guessing it would happen to (specifically) the Comet.
Americans and Brits (and others) all came to appreciate the durability of the Wildcat and Hellcat from the "Grumman Iron Works". But the Bearcat never saw WWII duty, and at least two F8F's broke up during postwar aerobatic exhibitions.
And Grumman's lunar vehicles were examples of outstanding performance-to-weight engineering, with just barely enough fatigue life to last one mission (that's certainly NO criticism of Grumman, just stating what they really accomplished!)
And the DC-10 problems were not fatigue-related at all, but overstress damage during unapproved maintenance procedures.
So, precious little of your original tome really addresses the current G-73 problem.
Enigmatologist
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News from Avweb reporter.
December 22, 2005
Cracks Found In Crashed Mallard's Spar
By Russ Niles
Newswriter, Editor
Investigators have found a major fatigue crack in the spar of the wing that separated from a Chalk's Ocean Airways turboprop Mallard on takeoff from Miami on Monday. The wing was recovered Tuesday and fatigue was quickly apparent. "We've seen fatigue. We don't know why that fatigue appeared. That is what we're trying to determine," Mark Rosenker, acting chairman of the National Transportation Safety Board, told reporters Wednesday morning. "This crack appears to extend through a majority of the spar at the location of the separation." A total of 19 passengers, most of them from the Bahamas, and the pilot died. Rosenker suggested the crack may have been hard to spot on a routine inspection. "Inspection maybe would have found that [metal fatigue], but there would have had to have been a very serious type of inspection to have understood it and found it," he said. The airline has suspended regular service but airline officials say there is still strong demand for flights and they hope to resume service by Friday. Chalk's has been in operation since 1919 and had three Mallards before Monday's crash.
This is going to take allot time to properly sort out. These guy's are my neighbours at FLL. These aircraft are very well maintained. The very fact that they have had such a safety record and their dependebility are testiments to the viability of the fleet. Many years ago I worked for Walker's Cay and I spent allot of time working on N2954 our Mallard. They are extremely well built and a sea kindly design. The next flying boat I worked on was the PBY. I licensed three of them and Imported two of them. I was luckey enough to amass about fifty hours in them. Just 'cause it's a highly experienced airplane does not make it trash. If it's properly maintained it can soldier on ad infinitum
My company ran twenty vintage airliners hauling the Wall Street Journal. Our mission completion rate was over 99.9% and we never hurt anyone. I only wish I still could operate them now.
Cracks Found In Crashed Mallard's Spar
By Russ Niles
Newswriter, Editor
Investigators have found a major fatigue crack in the spar of the wing that separated from a Chalk's Ocean Airways turboprop Mallard on takeoff from Miami on Monday. The wing was recovered Tuesday and fatigue was quickly apparent. "We've seen fatigue. We don't know why that fatigue appeared. That is what we're trying to determine," Mark Rosenker, acting chairman of the National Transportation Safety Board, told reporters Wednesday morning. "This crack appears to extend through a majority of the spar at the location of the separation." A total of 19 passengers, most of them from the Bahamas, and the pilot died. Rosenker suggested the crack may have been hard to spot on a routine inspection. "Inspection maybe would have found that [metal fatigue], but there would have had to have been a very serious type of inspection to have understood it and found it," he said. The airline has suspended regular service but airline officials say there is still strong demand for flights and they hope to resume service by Friday. Chalk's has been in operation since 1919 and had three Mallards before Monday's crash.
This is going to take allot time to properly sort out. These guy's are my neighbours at FLL. These aircraft are very well maintained. The very fact that they have had such a safety record and their dependebility are testiments to the viability of the fleet. Many years ago I worked for Walker's Cay and I spent allot of time working on N2954 our Mallard. They are extremely well built and a sea kindly design. The next flying boat I worked on was the PBY. I licensed three of them and Imported two of them. I was luckey enough to amass about fifty hours in them. Just 'cause it's a highly experienced airplane does not make it trash. If it's properly maintained it can soldier on ad infinitum
My company ran twenty vintage airliners hauling the Wall Street Journal. Our mission completion rate was over 99.9% and we never hurt anyone. I only wish I still could operate them now.
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Last edited by lamer; 23rd Dec 2005 at 15:00.
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attn: Barit1
I encourage you to read nevil shute (norway)'s book, "Slide Rule". While he was involved with dirigibles ( and his was the first to fly from England to Canada) his expertise also includes designing the first retractable gear aircraft in England.
As anyone who knows anything about metal fatigue the first transportation accident due to metal fatigue was in 1842.
Stress and fatigue are kissing cousins for the purpose of this discussion.
You noted that the DC10 crashed for one reason and don't seem to think that the MALLARD could( i say again could, no proof) have crashed because someone backed a forklift into its wing during changeover to turboprop engine.
I see that you have a commercial single engine land certificate.
Good for you. I see you are an engineer. (B&O?) but I digress.
Why did I mention Nevil Shute's great work? so that people who aren't engineers or pilots might get a laypersons appreciation for what happened east of Miami.
If you would like to argue finer points of aviation, you have my e mail address.
I'd like to point out that just a few weeks prior to the Three Mile Island meltdown or near Melt Down a little movie came out called, "The China Syndrome".
Sometimes people who can't prove something still want to shout a warning so that someone might be alert. A book or a film can sometimes do just that.
Nevil Shute did that with "No Highway" and subsequent movie. He also warned us of the terrible consequences of Nuclear War in "On the Beach".
One quote might even help everyone on this forum out:
"airplanes do not crash in and of themselves, perhaps one crash in a thousand is truly an act of God, instead they crash because men are irresolute, careless or reckless" (from "Slide Rule).
so barit1, post what you like. I don't think too highly of what you have said so far.
Oh and I see Bearcat fighters all the time here in Reno at the air races! And they were just coming into use as the bomb was dropped on H and N.
[email protected]
As anyone who knows anything about metal fatigue the first transportation accident due to metal fatigue was in 1842.
Stress and fatigue are kissing cousins for the purpose of this discussion.
You noted that the DC10 crashed for one reason and don't seem to think that the MALLARD could( i say again could, no proof) have crashed because someone backed a forklift into its wing during changeover to turboprop engine.
I see that you have a commercial single engine land certificate.
Good for you. I see you are an engineer. (B&O?) but I digress.
Why did I mention Nevil Shute's great work? so that people who aren't engineers or pilots might get a laypersons appreciation for what happened east of Miami.
If you would like to argue finer points of aviation, you have my e mail address.
I'd like to point out that just a few weeks prior to the Three Mile Island meltdown or near Melt Down a little movie came out called, "The China Syndrome".
Sometimes people who can't prove something still want to shout a warning so that someone might be alert. A book or a film can sometimes do just that.
Nevil Shute did that with "No Highway" and subsequent movie. He also warned us of the terrible consequences of Nuclear War in "On the Beach".
One quote might even help everyone on this forum out:
"airplanes do not crash in and of themselves, perhaps one crash in a thousand is truly an act of God, instead they crash because men are irresolute, careless or reckless" (from "Slide Rule).
so barit1, post what you like. I don't think too highly of what you have said so far.
Oh and I see Bearcat fighters all the time here in Reno at the air races! And they were just coming into use as the bomb was dropped on H and N.
[email protected]
The fracture photos point to stress raisers from holes, brackets or other drillings. Corrosion played no part whatever in this one.
The Vickers Viscount (VH-RMQ) that lost a wing in Western Australia in 1968 had spar stress raisers from sleeves through the spar that had been bashed in carelessly during major service.
The Vickers Viscount (VH-RMQ) that lost a wing in Western Australia in 1968 had spar stress raisers from sleeves through the spar that had been bashed in carelessly during major service.
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Chalk's pilot's husband sets up foundation
BY DARRAN SIMON
[email protected]
Mark Marks last talked to his wife, pilot Michele Marks, on Dec. 18 when they rose before sunrise and he made her coffee. He told her he loved her, and to fly safe.
He found out she died when he saw the report Dec. 19 on TV that a Chalk's Ocean Airways seaplane had crashed off Miami Beach.
The couple's memories always seemed to come on the water's edge.
They met on a nine-day shark behavior ecology course in a South Africa fishing town. He asked her to marry him on the 10th day. Michele became Mrs. Marks on the San Diego coast.
''Everywhere I walk I see her. I smell her,'' Mark Marks told reporters Saturday at their Boynton Beach home. ``She was my soul mate, my best friend and my wife.''
Marks, 42, a renowned zoologist and research biologist who works with white sharks, said his wife of more than seven years loved wildlife and the ocean. He plans to start the Michele Lynn Marks Marine Conservation Foundation to give scholarships to college students for marine research.
The right wing of Chalk's Flight 101 separated from the fuselage in the crash. The seaplane plummeted into the water near the Government Cut jetty off Miami Beach. It had just left Watson Island, heading to Bimini. The 18 passengers and 2 pilots on board were all killed.
The cause of the crash is not expected for some time. But the Federal Aviation Administration issued a bulletin Friday saying it may now require mandatory inspection of all seaplanes. The bulletin said an FAA preliminary investigation showed stress fractures in the 58-year-old Grumman G-73 Turbine Mallard seaplane's right wing support that could have played a role in the crash.
Chalk's voluntarily grounded its four other G-73 aircrafts after the National Transportation Safety Board discovered the fractures.
Mark Marks said he didn't know much about the investigation but has to be patient.
''I really want to know what happened, for her, her co-pilot, the families of the other 15 passengers and three children that died,'' he said. ``I don't know how to honor her better than to find out the truth.''
Michele Marks, 37, loved seaplanes and worked for Chalk's about three years, flying twin-engine Grumman G-73T Mallards.
Chalk's promoted Marks, who had an unblemished flying record, according to the FAA, from first officer to captain this year.
Her husband wore her white gold wedding band with a green emerald around his neck.
The ring was one of the few items he has received from the medical examiner.
``I don't know how I am going to do this without her.''
He sobbed while talking and held a photo of his wife wearing a pilot's uniform.
''This is the single-most difficult thing I ever went through,'' he said.
Marks was teaching the shark behavior ecology course in 1998 when he met his wife. She was a few inches taller and attractive, he recalled. ''Oh man, I'm in trouble,'' he remembered saying when he first saw her.
They married on Sept. 23, 1998 -- her birthday.
She tempered him. He was loud, she was less confrontational. She wasn't the cook or the domesticated one. In fact, she just learned to boil spaghetti. She usually left a trail a clothes on the floor on her way to the shower.
She was the adventurer -- hiking mountains, swiming with white sharks in South Africa.
''She was fearless. She was absolutely fearless,'' her husband said.
He introduced her to hiking. They spent three months hiking across the country on their honeymoon. She was teaching him how to sail.
''I've lost my teacher as well,'' he said. She helped steer the Chondros, a 38-foot Irwin he owned from Naples to South Florida. The Chondros -- Latin for ''cartilaginous fish'' -- is docked at the couple's Boyton Beach complex.
The family held a service for her on Friday. Chalk's employees, mechanics, customs agents, and others from Bimini and passengers who flew with Marks showed up.
''I just feel so lonely without her,'' he said. ``She'll never come home, but I want her to come home so bad.''
http://www.miami.com/mld/miamiherald/13481687.htm
BY DARRAN SIMON
[email protected]
Mark Marks last talked to his wife, pilot Michele Marks, on Dec. 18 when they rose before sunrise and he made her coffee. He told her he loved her, and to fly safe.
He found out she died when he saw the report Dec. 19 on TV that a Chalk's Ocean Airways seaplane had crashed off Miami Beach.
The couple's memories always seemed to come on the water's edge.
They met on a nine-day shark behavior ecology course in a South Africa fishing town. He asked her to marry him on the 10th day. Michele became Mrs. Marks on the San Diego coast.
''Everywhere I walk I see her. I smell her,'' Mark Marks told reporters Saturday at their Boynton Beach home. ``She was my soul mate, my best friend and my wife.''
Marks, 42, a renowned zoologist and research biologist who works with white sharks, said his wife of more than seven years loved wildlife and the ocean. He plans to start the Michele Lynn Marks Marine Conservation Foundation to give scholarships to college students for marine research.
The right wing of Chalk's Flight 101 separated from the fuselage in the crash. The seaplane plummeted into the water near the Government Cut jetty off Miami Beach. It had just left Watson Island, heading to Bimini. The 18 passengers and 2 pilots on board were all killed.
The cause of the crash is not expected for some time. But the Federal Aviation Administration issued a bulletin Friday saying it may now require mandatory inspection of all seaplanes. The bulletin said an FAA preliminary investigation showed stress fractures in the 58-year-old Grumman G-73 Turbine Mallard seaplane's right wing support that could have played a role in the crash.
Chalk's voluntarily grounded its four other G-73 aircrafts after the National Transportation Safety Board discovered the fractures.
Mark Marks said he didn't know much about the investigation but has to be patient.
''I really want to know what happened, for her, her co-pilot, the families of the other 15 passengers and three children that died,'' he said. ``I don't know how to honor her better than to find out the truth.''
Michele Marks, 37, loved seaplanes and worked for Chalk's about three years, flying twin-engine Grumman G-73T Mallards.
Chalk's promoted Marks, who had an unblemished flying record, according to the FAA, from first officer to captain this year.
Her husband wore her white gold wedding band with a green emerald around his neck.
The ring was one of the few items he has received from the medical examiner.
``I don't know how I am going to do this without her.''
He sobbed while talking and held a photo of his wife wearing a pilot's uniform.
''This is the single-most difficult thing I ever went through,'' he said.
Marks was teaching the shark behavior ecology course in 1998 when he met his wife. She was a few inches taller and attractive, he recalled. ''Oh man, I'm in trouble,'' he remembered saying when he first saw her.
They married on Sept. 23, 1998 -- her birthday.
She tempered him. He was loud, she was less confrontational. She wasn't the cook or the domesticated one. In fact, she just learned to boil spaghetti. She usually left a trail a clothes on the floor on her way to the shower.
She was the adventurer -- hiking mountains, swiming with white sharks in South Africa.
''She was fearless. She was absolutely fearless,'' her husband said.
He introduced her to hiking. They spent three months hiking across the country on their honeymoon. She was teaching him how to sail.
''I've lost my teacher as well,'' he said. She helped steer the Chondros, a 38-foot Irwin he owned from Naples to South Florida. The Chondros -- Latin for ''cartilaginous fish'' -- is docked at the couple's Boyton Beach complex.
The family held a service for her on Friday. Chalk's employees, mechanics, customs agents, and others from Bimini and passengers who flew with Marks showed up.
''I just feel so lonely without her,'' he said. ``She'll never come home, but I want her to come home so bad.''
http://www.miami.com/mld/miamiherald/13481687.htm
The fracture photos point to stress raisers from holes, brackets or other drillings. Corrosion played no part whatever in this one.
Corrosion can occur anyplace, especially in drilled holes after- production where the surface may have a course texture. Of course I would not care to extrapolate from a internet photo. However the two different sides of the hole do appear to have two different types of fatigue initiations at their surface which in my view could possibly consider abusive machining or corrosion on one side and secondary initiation on the other.
I’m only a pilot, but I presume that the question on the engineering community's mind is why there are two offset drill holes in this particular location which have removed so much material (say 15% of the width) from the horizontal leg of the lower spar cap. The drill work does not look very skillful in my inexpert opinion.
Again IMHO, I venture to speculate that fatigue induced failure (whether corrosion related or not) would seem to have been an inevitable consequence and just a matter of time and cycles, once these offset drill holes were made.
Again IMHO, I venture to speculate that fatigue induced failure (whether corrosion related or not) would seem to have been an inevitable consequence and just a matter of time and cycles, once these offset drill holes were made.
No engineer am I - but I have to wonder at what appear to be two drill holes, not parallel to each other and apparently merging together. I sometimes achieve the same effect in a wall when installing an Ikea curtain rod. It would seem to me that such an action would create a stress concentration.
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Given the nature of the defect that apparently initated the crack, why is the inspection limited to Turbo Mallards? Why not R-1340 powered ones?
(I could even ask - why limited to Mallards?)
(I could even ask - why limited to Mallards?)