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Have been eyeballing Maules for float work.

Some time just for fun, pull a 185 and a Maule side by side and lay out a pallet of moose antlers or large drums of fuel. Go ahead and start loading and see which plane is easier!

Nothing like having the entire side open up for making loading easy!
 
I'd go fly one now on floats...like in Florida at Brown's, Florida Seaplanes mentioned earlier, or wherever the water's warm and wet? Ask about maintenance and explore the envelope. Maybe find a similar Cessna and test it too. Nothing like back to back to end the speculation.

Gary
 
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At least a couple were in a question about structural failure...one near the Etiviluk River/North Brooks Range and one near Sithlymenkat Lake near the Yukon River/Pipeline crossing. Both experienced pilots. Nothing more to add and it's history not to be repeated. Some talk about certification stress tests prior, turbulence, or fuel and whatever. Airport chatter. Knew them both but it happens and not sure why. Just my recollection.

Gary
 
A friend of his was killed by a Maule, structural failure. They are a cheaply made aircraft, not sure how they were certificated that way?

There are limitations to any aircraft. Borrowing from an older post I copied and pasted the NTSB Number below. 80mph winds with higher gusts, float plane, two occupants not certain on how much fuel and gear aka gross weight at the time.

ASF Accident Details
8/23/1996
NTSB Number: ANC96FA131
Aircraft and Flight Information
Make/Model MAULE / M-4/5/6/7
Tail Number N5656A
Airport N/A
Light Conditions Day
Basic WX Conditions VMC
Phase of Flight Cruise

As an FYI I don't believe that Maule wing skins are considered structural. I'm very sorry to hear friends were lost, I'm pretty sure that the majority of us have had one or two "But for the Grace of God Moments" planes are machines and they have limits, Maules are certified through the same FAA process as all the rest. when we push those limits we're test pilots. Lots of factors here that I think are unknown. Here's the definition of severe and extreme turbulence:

The definition for severe turbulence includes the sentence: “Aircraft may be momentarily out of control.” Extreme turbulence is defined as “turbulence in which the aircraft is violently tossed about and is practically impossible to control. It may cause structural damage.

This is my opinion, I realize there's others.


Sent from my iPad using SuperCub.Org mobile app
 
At least a couple were in a question about structural failure...one near the Etiviluk River/North Brooks Range and one near Sithlymenkat Lake near the Yukon River/Pipeline crossing. Both experienced pilots. Nothing more to add and it's history not to be repeated. Some talk about certification stress tests prior, turbulence, or fuel and whatever. Airport chatter. Knew them both but it happens and not sure why. Just my recollection.

Gary

One incident of structural failure, well documented here already.
The other, I believe, was attributed to poor maintenance - wing strut corrosion was the culprit, also well documented.
(the wing folded up when the pilot did a low flyby over his cabin)
 
There are limitations to any aircraft. Borrowing from an older post I copied and pasted the NTSB Number below. 80mph winds with higher gusts, float plane, two occupants not certain on how much fuel and gear aka gross weight at the time.

ASF Accident Details
8/23/1996
NTSB Number: ANC96FA131
Aircraft and Flight Information
Make/Model MAULE / M-4/5/6/7
Tail Number N5656A
Airport N/A
Light Conditions Day
Basic WX Conditions VMC
Phase of Flight Cruise

As an FYI I don't believe that Maule wing skins are considered structural. I'm very sorry to hear friends were lost, I'm pretty sure that the majority of us have had one or two "But for the Grace of God Moments" planes are machines and they have limits, Maules are certified through the same FAA process as all the rest. when we push those limits we're test pilots. Lots of factors here that I think are unknown. Here's the definition of severe and extreme turbulence:

The definition for severe turbulence includes the sentence: “Aircraft may be momentarily out of control.” Extreme turbulence is defined as “turbulence in which the aircraft is violently tossed about and is practically impossible to control. It may cause structural damage.

This is my opinion, I realize there's others.


Sent from my iPad using SuperCub.Org mobile app

That NTSB report was based largely on testimony of a couple of non pilots who probably couldn’t tell a 20 mph wind from a 80mph wind. And completely ignored the testimony of two people the pilots left on a lake nearby, who testified the wind there was virtually calm. 80 mph winds and extreme turbulence just a few miles from where the winds were virtually calm.

It also ignored the fact that the accident airplane wS in fact the flight test prototype for the M-7 design. Which means that airplane had been subjected by the factory to stresses in all probability beyond “normal” limits, before it was sold.

After this accident,in which top wing skins departed the aircraft (as opposed to a wing coming off), an FAA Inspector examined a number of Maules and noted smoking rivets in top wing skins.....some would call that a “clue”. But, that Inspector was told to stop looking, and NTSB never mentioned this, nor did they follow up.

The Maule M-5 accident Gary mentioned at Sithleminkat Lake was called a stall/spin loss of control accident by NTSB, even though there were clear skid marks down the hill preceding the crash site. The NTSB chose to ignore pertinent information developed by the husband of the pilot of that airplane......information which has the potential for saving a life.

That was when I stopped taking NTSB reports as gospel. If it’s a report about an airliner accident, they pull out all the stops and try to get to the actual cause. In general aviation accidents, the NTSB seems to at least occasionally be satisfied to ignore potentially important data, on their way to a “pilot error” conclusion. There is no doubt that in the latter case I noted that pilot error was the proximate cause of the accident, but there was no stall/spin, and there was information presented that was ignored. Information which could be a factor in future accidents.

MTV
 
MTV,

I would like to hear more about the 'Life Saving Information' you mention; Might be my life I save.

Any aircraft has the potential to kill us, as can any automobile.

I agree that if you look at almost any Maule with some time on it, you can find a smoking rivet or two on the top of the wing, on most Cessna 180/185 and piper Six series aircraft you will find cracked skins along the spar line after some time- the six in a few thousand hours, the cessnas usually take a little longer.

Our forums are full of questions about stuff that will kill us not working correctly. How many fuel system questions have we had about Cessnas not working correctly? Locally we had a 207 last fall hit the water due to a fuel issue.

How many engine troubles have been asked about in all types of aircraft?

Bottom line, no matter who made it and how new or old your aircraft is, taking the time to inspect it, money and effort to maintain it, and flying within it's envelope can save lives- maybe your own.
 
The wing skins on a maule are too thin, they all crack in the prop wash area... Not sure why they are made this way? Maybe weight saving is more important to them than keeping a lift surface intact. Not a pretty picture after one fails...To each his own, I won't work on or fly them.
 
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We could cherry pick incidents where just about every make and model of aircraft has fallen out of the sky.
Off airport is a tough environment, often stressing ac beyond design limitations. Seemingly harmless
cumulative stresses can add up and result in unexpected failure during mundane ops.
Ultimately up to the PIC to consider maintenance history and conditions AC has been subjected to.
Maule was purpose built for hauling big loads into short strips, as such, most have had the crap beat out of them. They need to be maintained and inspected accordingly. Last two Maule’s I had would carry more fuel in the wings than a Cubs total useful load, half of that weight was in outboard tanks. Built like a truck.
If you are not comfortable getting in a Maule then don’t.
 
The wing skins on a maule are too thin, they all crack in the prop wash area... Not sure why they are made this way? Maybe weight saving is more important to them than keeping a lift surface intact. Not a pretty picture picture after one fails...To each his own, I won't work on or fly them.

So maybe, like everyone replacing fuselages and struts on a Supercub, people should be more diligent about replacing the skins on the Maule wings with thicker metal and better rivets.
 
So maybe, like everyone replacing fuselages and struts on a Supercub, people should be more diligent about replacing the skins on the Maule wings with thicker metal and better rivets.

Let's not get to the rabbit hole of landing gear beef ups, x brace on top and seat belt attach points8)

Nope, no weak points on the cubs at all!:wink:

(and how about the box brace in the tail?)
 
My cub went almost 40 years out of the factory before rebuild. Don't try that with a maule, she ain't no Georgia peach...
 
My cub went almost 40 years out of the factory before rebuild. Don't try that with a maule, she ain't no Georgia peach...

No argument from me on that. I still trust the original Cubs. One big issue I had with the original Husky's too. Too many Pop Rivets. Can't believe the FAA even allows that.
So there is now a whole industry waiting out there to rework Maules, like there is Tricking out Cubs.
 
We could cherry pick incidents where just about every make and model of aircraft has fallen out of the sky.
Off airport is a tough environment, often stressing ac beyond design limitations. Seemingly harmless
cumulative stresses can add up and result in unexpected failure during mundane ops.
Ultimately up to the PIC to consider maintenance history and conditions AC has been subjected to.
Maule was purpose built for hauling big loads into short strips, as such, most have had the crap beat out of them. They need to be maintained and inspected accordingly. Last two Maule’s I had would carry more fuel in the wings than a Cubs total useful load, half of that weight was in outboard tanks. Built like a truck.
If you are not comfortable getting in a Maule then don’t.

My primary point earlier was simply that when people start citing NTSB reports, a lot of folks take those as gospel. I for one have seen these two that happened to be Maules, and a couple others, where the NTSB clearly erred in at least some of their conclusions.

In the Maule accident where the wing came apart, the wing itself didn't "fail", the top wing skin literally departed the aircraft. That airplane would have been subjected to Vd dives during it's flight test life, and was then sold to a customer.

Look carefully at the top skins on any Maule that has many hours on it. Those wings are essentially "metalized fabric covered wings". The spars are tough, no doubt, but the earlier Maules have very thin wing skins. Now, take a look at the rivet spacing on those top skins.....those rivets are a long ways apart. Those skins are thin, and the rivet spacing is HUGE.

A friend of mine owned an M-7, and worked it pretty hard. He essentially doubled the number of rivets in the wing skins.....a lot of work, but he knew those gents that were killed in the accident we've been discussing.

I have flown Maules, and I'm sure not afraid of them. They perform great, no doubt. As others have noted, one needs to maintain them. Duh.

The fuselage and tail surface fabric work from the factory is pretty poor, though they've improved a bit in recent years. I've flown a few Maules that've had the fuselage re-covered and repainted, and those are generally really nice airplanes.

Most of my Maule time is on floats, and they typically don't have a lot of useful load in that configuration.....either gas or cabin load, but not lots of both. That's not a criticism, just a comment. Neither does a stock Cub.

They can be great airplanes, and as I noted, they really perform well. Just keep an eye on those top wing skins......

MTV
 
MTV,

I would like to hear more about the 'Life Saving Information' you mention; Might be my life I save.

George,

It's a very long story. The engine failed in that aircraft, in a pretty bad place and situation. It failed because water was delivered into the fuel system.

Specifically, as is often the case, the wing tip tanks were filled at a different time than the main tanks. The bulk tank had fuel delivered between these two fillings, and the lid was left off this stand mounted tank. It rained buckets for several days between the bulk tank fill up and the pilot filling the outboards with fuel, which turned out to be contaminated with water (samples were taken from the hose, which had a lot of water in it).

The pilot flew family members to a lake where they had a fuel cache in cans. It was verified that the cache was intact after the accident.....none had been used. After takeoff from the lake, the pilot was climbing out from the lake (which sits in a bowl) when the engine failed. They negotiated a 180 degree turn while attempting an engine restart, but impacted the surface before reaching the lake. There were clear skid marks where the floats slid on the hill side, but the airplane stubbed, and wound up inverted. There were no survivors.

The co-owner of the airplane arrived on the scene while NTSB was examining the wreckage, and the NTSB rep. released the wreckage to him when they were done with the exam.

The owner examined the wreckage and found that both aux tank pumps had been energized when the accident occurred. The fuel tanks had been ruptured during the accident, but the fuel lines from the aux tanks to the mains were crimped and cut out, and tested. They both contained water.

So, apparently, the pilot had fueled the tip tanks on the day of the accident. On climb out from their stop over, the pilot energized both outboard fuel pumps simultaneously, which is consistent with recommendations in the Maule POH.

This information, plus pictures showing the skid marks leading to the wreckage were presented to the NTSB. They ignored it, and their final determination was, incredibly, a stall/spin.

After this episode, when I fly a Maule and intend to use the outboard tanks, I pump one main down first, switch the selector to the other main, then pump SOME fuel from the outboard on the side I just fed fuel from to the main. Then I shut off the outboard transfer, and switch back to that main.....while cocked and locked, and ready for an engine failure, and ready to switch the fuel selector back to the other main. In this case, the pilot inadvertently contaminated ALL fuel tanks by energizing both transfer pumps at once.

Now, understand that I don't consider this a Maule "Deficiency". I (and the co-owner of the plane in question) just feel like there should be a cautionary note in the POH about this.

There was no way to verify that the pilot sumped the outboards after they were filled that day....that can be a pain on floats, but a few people who knew the pilot (including me) had seen the pilot do so on other occasions. In any case, I have had water in fuel tanks that was REALLY hard to get out via the sump drains. Consider that the new Cessna 172s have over a dozen sump drains in their fuel system.... So, it's quite possible that the sumps were drained, but not all the water was removed, especially on floats, where the plane may or may not be totally level while sumping.

To me, the take away from this accident is to NOT energize both tip tank pumps at once. Verify you're getting clean fuel from one tip before you transfer fuel from the other.

Granted, the likelihood of duplicating this accident is really low, but an engine failure any time can lead to really bad consequences.

MTV
 
It's been 40 yrs since my M-5 but I recall the outboard fuel tank transfer pumps (2) had a removable filter screen on their bottom. It took a socket wrench and some turning or just a twist-off maneuver. I think there were both aux and of course main tank sump drains. There may have been a low point in the fuel line drain(s-?). Never flew one on floats but it may have been a chore to remove debris and water from the outboard.....and who pulls the pump screen routinely? Once water mixes in with fuel then what to do? Sad deal.

My upper wing rivets on mine smoked during flight in rain and the paint flaked off. But the big oops was the fuel line under the seat that got crushed by the flap lever when pulled. I think they fixed that in later S/N's.

Sure was fun to fly. We put whole cleaned mulligan moose inside w/o the legs, innards, and head attached.

Gary
 
To me, the take away from this accident is to NOT energize both tip tank pumps at once. Verify you're getting clean fuel from one tip before you transfer fuel from the other.

Granted, the likelihood of duplicating this accident is really low, but an engine failure any time can lead to really bad consequences.

MTV[/QUOTE]

Very unfortunate for the folks involved.
To me the takeaway from this accident is to avoid contaminated fuel, sump all tanks prior to flight and following refueling. Being on floats does not excuse one from sumping outboard tanks, especially if your life depends on the fuel in them.
Not sure why this has any bearing on a specific make and model of aircraft, Cubs dont run well on water either.
Can we move on now..
 
Sorry to rant,
i own a cub now and love it. Tired of all the bashing Maule’s have taken over the years.
Like I said earlier, if you don’t like them don’t get in them, pretty simple.
You wouldn’t catch me dead in a Husky though..😉
 
Here is the NTSB report of the accident referred to above.

https://www.ntsb.gov/_layouts/NTSB....ev_id=20010813X01678&ntsbno=ANC01FA084&akey=1

Some parts of it are as follows:

The engine cowling, fuselage firewall, and the instrument panel were crushed and displaced aft. The engine was partially buried in the soft, tundra-covered terrain. The engine sustained extensive impact damage to the underside, and lower front portion. The carburetor assembly was broken free from the mounting plate. An internal examination of the carburetor bowl contents revealed about 10 cc of clean, uncontaminated fuel. The fuel sample collected from the carburetor bowl tested negative when subjected to water detecting paste.

The firewall mounted, glass, gascolator bowl was found intact and was completely full of clean, uncontaminated fuel. The fuel sample collected from the firewall mounted gascolator tested negative when subjected to water detecting paste. The gascolator screen was free of contaminants.

It's worth a read in light of what is being said.

Jerry
 
Oliver,

That accident was mentioned earlier by another poster. I noted that it was not a mechanical failure. I was then asked to explain the cause of that accident by a current Maule owner, which I did.

You are correct about dumping tanks. That said, try sumping those tip tanks properly with the plane on floats, it can be a losing task, unless you happen to have a dock handy, and sometimes even then.....

But, my point was not to point any fingers at Maules. And not trying to put that accident on the airplane. Mistakes were made, and the consequences were fatal. I don’t know about you, but I too have made mistakes in an airplane, but I was fortunate to survive. If I were to perish in an airplane, I sincerely hope someone would try to find out what went wrong and learn from it.

As a side note, I had a conversation via email about Maules with Alex before he started this thread. I offered him my perspective there on Maules, and as I recall, I suggested the airplane might work well for his operation.

In general, I don’t bad mouth airplanes. I ascribe to the philosophy about favorite airplanes shared by Adolph Galland, the famous fighter general of the Luftwaffe, with a reporter years after the war. The reporter asked Galland what his favorite airplane was. The General’s response was: “The airplane I was flying that day.”

A good philosophy.

MTV
 
Here is the NTSB report of the accident referred to above.

https://www.ntsb.gov/_layouts/NTSB....ev_id=20010813X01678&ntsbno=ANC01FA084&akey=1

Some parts of it are as follows:

The engine cowling, fuselage firewall, and the instrument panel were crushed and displaced aft. The engine was partially buried in the soft, tundra-covered terrain. The engine sustained extensive impact damage to the underside, and lower front portion. The carburetor assembly was broken free from the mounting plate. An internal examination of the carburetor bowl contents revealed about 10 cc of clean, uncontaminated fuel. The fuel sample collected from the carburetor bowl tested negative when subjected to water detecting paste.

The firewall mounted, glass, gascolator bowl was found intact and was completely full of clean, uncontaminated fuel. The fuel sample collected from the firewall mounted gascolator tested negative when subjected to water detecting paste. The gascolator screen was free of contaminants.

It's worth a read in light of what is being said.

Jerry

Jerry,

That is indeed the report for the accident in question. That said, the fuel lines between the mains and tip tanks contained water, both fuel transfer switches were energized, the engine was not running, and the pilot was attempting a restart with the key switch. We could only assume that the gascolator had been purged of water, but not in time to complete a restart.

The report also notes: "On August 9, 2001, an engine examination and disassembly was conducted at Chena Marina Air Service, Inc., in Fairbanks. No preimpact mechanical anomalies were noted during the examination of the engine, or engine accessories." So, the engine failed, but not for any detected mechanical reason.

I'll leave this here. This was a tragedy, no doubt. I lost a lot of faith in the NTSB over this one.

MTV
 
Side track:

I believe another thread could be opened to discuss fuel and contamination issues.

As instructors we teach sumping fuel; but do we do it justice by showing what really to look for? We often show a small bubble of water separated from the fuel, but what about when sumping and the water has not separated?

What about when you sump and all that comes out is actually water? Do we show that to our students?

Water and contaminates are a bad thing, and many of us get lazy when we pull up to the fuel pumps with all the fancy filters thinking what we put in our tanks is just fine- once in a while it is not.

Water block filters are important and great- but nothing is foolproof.

Almost every large turbine in the world has multiple tanks and must move fuel from one to the other in flight- not rocket science here. But it is very important to ensure your fuel is clean going into the tank.

If you are flying a plane with your fuel tank inside the cabin, (champs, Tcraft, J-3), every time in the winter you warm the cabin and tank you create moisture in your tank through condensation, let her sit and get below freezing that condensation becomes ice. If you park outside and sump your tanks in the morning you will get no impurities, but once the tank is warm that ice becomes liquid... Moral is to sump at the end of the day!

Thank you MTV for the information. I will change how I transfer fuel, sounds like good advice for any aircraft with multiple tanks.
 
A couple questions please for current owners before we leave regarding M-5-235 carb or similar.

The fuel selector has 4 positions...L/R/Both/Off. The Flight Manual info has changed over time for takeoff and landing on the fullest tank to the later option for both if they are similar level. What's the latest procedure for fuel tank selection?

There's both an engine driven and electric aux main fuel boost pressure or transfer pump (from memory but may be wrong). What's the latest procedure for maintaining adequate minimum fuel pressure (0.5 psi in the SM I believe) during extended full power climbs at minimum fuel or during a mechanical fuel pump failure?

And that old fuel line behind the activated flap handle SB to watch for crushing and reduced fuel flow was the right tank to fuel selector line I think. Haven't seen a fuel system diagram yet. Switching to a fuller tank on engine hesitation is common and often accompanied by activating the electric boost pump even for carbs.

Some early Maules came with 1/8" NPT plugs where the quick drains could later be installed in the fuel tanks.

Gary
 
Alex, Have you considered a 172XP which has a higher gross than your old 172N? I had one on EDO 2440s for a while, it could carry a load with good performance. My wife used it for teaching seaplane ratings.
 
A couple questions please for current owners before we leave regarding M-5-235 carb or similar.

The fuel selector has 4 positions...L/R/Both/Off. The Flight Manual info has changed over time for takeoff and landing on the fullest tank to the later option for both if they are similar level. What's the latest procedure for fuel tank selection?

There's both an engine driven and electric aux main fuel boost pressure or transfer pump (from memory but may be wrong). What's the latest procedure for maintaining adequate minimum fuel pressure (0.5 psi in the SM I believe) during extended full power climbs at minimum fuel or during a mechanical fuel pump failure?

And that old fuel line behind the activated flap handle SB to watch for crushing and reduced fuel flow was the right tank to fuel selector line I think. Haven't seen a fuel system diagram yet. Switching to a fuller tank on engine hesitation is common and often accompanied by activating the electric boost pump even for carbs.

Some early Maules came with 1/8" NPT plugs where the quick drains could later be installed in the fuel tanks.

Gary

Mine only has Left, Right and off, no both.

Transfer pumps only transfer from tips (Aux) tanks to mains. Gravity and engine pump I believe pump in normal operations, but if pressure drops the electric pump will increase pressure between gascolater and the carb.

My fuel line from right tank runs under the seat, but up and out of the way of the flap handle. I will look again, but seems it is well out of the way.
 
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