WSJ 04/30/2001 Cessna Fuel System

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WSJ 04/30/2001 Cessna Fuel System

Postby MoonlightVFR » Wed Jan 10, 2018 4:46 am

Just reread article.

Strong against Cessna' s restart to single engine aircraft production.

Intimated wet wing fuel system was flawed.

Cessna paid $775,000 in 1987 , crash, death, watery fuel. older design. Good attorney.

Am I reading this correctly , that current 172s have 13 different drain points?

My C170 has 3 points 1 ea wing and the gascolater.

From that long ago friction between FAA/Cessna is anything different today for C170 operators?
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby gahorn » Wed Jan 10, 2018 4:53 pm

The water-in-fuel problem in the article refers to airplanes mfr'd with wet-wing fuel tanks mfr'd since 1996. Cessna had suffered a previous problem with bladder-tanks in C182s and C177s (Skylanes and Cardinals) as wrinkles in the bladders would retain "puddles" of water, ...and when single-engine production began again they addressed the issue by using "wet-wing" fuel tanks in which the wing-skin itself formed the fuel tanks. This is a common method in larger airplanes. Cessna found that some water could still be trapped by internal wing ribs so they offered an upgrade kit that installed 4 more drains in each wing.

One more reason I like my 1950s Cessna 170 and it's original viewing-glass gascolator.

The WSJ article is reprinted below:

Cloud Hangs Over Cessna's Revival Of Popular Single-Engine Planes
By Jerry Guidera Staff Reporter of The Wall Street Journal
Updated April 30, 2001 11:59 p.m. ET

(See Corrections & Amplifications item below.)
After Brad Schroeder crashed while piloting a single-engine Cessna Skyhawk near Chicago in 1991, investigators from the National Transportation Safety Board added insult to injury.
They faulted Mr. Schroeder, who nearly died in the crash, saying he had failed to perform the proper preflight safety routine for draining water from the fuel tank. The investigators had concluded that water from the tank had entered the Skyhawk's engine, shutting it off at 1,100 feet. But Mr. Schroeder insisted that he had followed the preflight instructions to the letter, including the draining regime. The NTSB finding "didn't make any sense to me," he says.
Now, the Federal Aviation Administration has taken action that may shed further light on this and similar crashes over the years. Prompted by pilots and recent incidents that have raised suspicion, the FAA is conducting tests to determine if the fuel system in several popular Skyhawk models is defective and prone to delivering water to the engine.
Threat to Business

For Cessna Aircraft Co., the FAA's tests pose a threat to what has been the successful rejuvenation of its single-engine business, restarted in 1996 after a 13-year shutdown. In 1983, Cessna shuttered its single-engine operation, blaming an onslaught of product-liability lawsuits, some of which alleged defective fuel tanks. In 1994, after years of intense lobbying by Cessna and others, President Clinton signed into law the General Aviation Revitalization Act, which gave single-engine aircraft manufacturers like Cessna broad immunity from liability lawsuits. Cessna resumed production at a new plant in Independence, Kan.
A unit of Textron Inc., Cessna insists that its planes are safe and says it expects the tests will prove that. An FAA spokeswoman says preliminary results from the tests, which are continuing, indicate that the aircraft pose no immediate danger to pilots who perform a proper preflight check.

By far the largest American manufacturer of single-engine propeller airplanes, Cessna says as many as 20,000 aircraft -- which range in price from about $144,000 to $300,000 -- incorporate the fuel-tank structure under investigation. More than 100,000 single-engine Cessna planes, flown primarily for recreational purposes and by small businesses, are in use in the U.S. Cessna, which makes most of its money from selling expensive jets to business customers, contributed more than 20% to Textron's $13 billion in revenue last year, up from barely 10% eight years ago.
A Review of Accidents
The NTSB has put its database for all U.S. air accidents since 1983 online. A review of those reports for the five years since Cessna resumed single-engine production turns up a total of 2,149 accidents involving single-engine Cessna planes. Of those, 25 were at least partly caused by watery fuel, with two resulting in deaths, federal investigators said.
NTSB accident database
http://nasdac.faa.gov/asp/fw_ntsb.asp
The pilot in each case had failed to perform proper preflight checks of the tanks, the investigators said. They also found water in the fuel system in 29 other Cessna aircraft involved in crashes during the period, some of them fatal, in which the cases are still under review or were closed without determination of cause.
Cessna, based in Wichita, Kan., declined to comment on the NTSB records. But it said in a statement responding to questions that fuel contamination is "an aviationwide issue," and that the company has worked diligently to inform pilots of how to find and deal with water in the fuel. Cessna single-engine "tanks are designed and continuously improved to make it as easy as possible, if proper preflight procedures are followed, to detect and remove all hazardous amounts of water," the statement said.
Divided on Safety
"Our kids fly in these, our wives," says Steve Copeland, a Cessna engineer who is the company's liaison to the FAA investigation. "We're not going to get into these airplanes unless they're safe."
But some aviators, relatives of crash victims and others say that the planes are flawed and the review is long overdue. They also say that the tests, which focus only on a newer type of fuel tank, should be broadened to include an older tank design. Large numbers of both tanks are in use, and together the two designs account for most of the single-engine Cessnas in the American market.
"Cessna has tried to bury its head in the sand over this issue," says Richard French, a Cleveland attorney who has handled liability cases for and against the aircraft manufacturer. In 1987, Mr. French reached a $775,000 settlement with the company after alleging in a lawsuit that a Cessna that crashed near Elyria, Ohio, went down because of water in the engine caused by a defective fuel tank. The 1986 crash, which involved an aircraft with one of the older-design tanks, killed the pilot, Scott Marx, and injured three family members. Cessna declined to comment on the case.
Keeping water out of the fuel system is a problem that has faced aviation since its inception. Water can get into an airplane's tank accidentally in a number of ways, including condensation released from the fuel under rapid outside temperature changes, seepage from a loose overhead gas cap or cracks in a wing, or by refueling with a source already contaminated by water. When water reaches the engine, it can snuff out combustion, causing a shutdown.
Cessna pilots are told in training and operating manuals to check the fuel system for water during preflight preparations. On new models of the Cessna Skyhawk, the most popular single-engine aircraft in the U.S., this involves opening a total of 13 sumps, or drains, at various low points in the fuel system. The idea is that water, which is heavier than airplane fuel, will sink to the low spots. New Skyhawks carry their fuel enclosed in hollows in each wing called integral tanks, or wet wings. Each of the two 28-gallon tanks carries five sumps at various locations along the belly of the wing. The three remaining drains are farther down the fuel system.
Cessna began installing wet wings in 1967, gradually replacing a design that stored the fuel in a rubber bladder inside the wings. Pilots liked the new design because it boosted fuel-carrying capacity and allowed longer trips. Cessna says it has had fewer reports of accidents with the wet-wing planes than with the bladder-equipped models. "It's been a great system for us," says Stanley J. O'Brien, head of propulsion for Cessna's single-engine operations.
'Rock and Roll'
Both designs have been the subject of Cessna and FAA safety actions over the years. In 1982, Cessna began including in its flight manual for single-engine Cessnas new preflight instructions about drainage, which were also included in a service bulletin to owners of older models. If water was detected after an initial opening of the drains, pilots were instructed to "gently rock" the wings and to lower the tail "to move any additional contaminants" to the drains. The routine, which came to be known as the "rock and roll" procedure, remains a part of recommended preflight preparation.
In 1983, the FAA issued one of its rare Airworthiness Directives, ordering owners of most bladder-equipped, single-engine Cessnas to check the bladders for "any wrinkles which retain fluid after draining" and to replace them as needed. The reason for the order, the FAA said, was "to prevent power loss or engine stoppage due to water contamination of fuel system." Cessna issued a similar warning that year.
In 1992, Cessna issued a service bulletin to owners of aircraft with wet wings warning them about water-related problems and offering owners kits, sold at cost, for installing four additional drains under each tank "to assist in the detection and removal of water." Cessna hoped the drains would make the preflight check "idiot-proof," says Mr. Copeland. Cessna also issued a reminder bulletin offering the new drains in 1996.
Over the years, Cessna says it has faced between 40 and 50 suits alleging that water from the bladder cells contributed to crashes. All those suits have been resolved, and the company says it hasn't faced a new suit in six years.
Eugene Odou, a retired doctor in Montebello, Calif., and a former medical examiner for the FAA, says his daughter Carol was killed in a 1983 water-fuel accident involving the family's Cessna 182P. This single-engine plane is a bit bigger than the Skyhawk and equipped with bladder tanks. Her husband, William Tatnall, who was the pilot, says he found water during the preflight check and then performed the rock-and-roll procedure before the fateful flight. He sued Cessna, contending that flaws in the bladder made it impossible to drain water that had seeped into one of the wing's fuel tanks.
The two sides reached an out-of-court settlement, say Messrs. Odou and Tatnall, who declined to disclose terms. Later that year, the FAA issued the bladder Airworthiness Directive. Cessna declined to comment on the crash or the lawsuit.
The recent regulatory attention was sparked in August 1998, when the engine of a Cessna piloted by Robert E. Scovill Jr. stopped in midflight, forcing an emergency landing in a farmer's field near Mr. Scovill's home in Smyrna, Tenn. He said it was the third time that he had had an in-flight engine hesitation with the plane, a wet-wing Skyhawk built in 1981.
For help, Mr. Scovill, a general contractor, called the FAA's office in Nashville, which dispatched inspector George Erdel. Together with Mr. Scovill's mechanic, they went through a standard preflight drainage check. Then Mr. Scovill tried to take off on a makeshift runway, but the engine sputtered to a halt. After Mr. Erdel checked the sumps for water again, he removed about a pint of water from the drains, he and Mr. Scovill say.
Mr. Scovill drained the fuel system completely, swabbed the tank with alcohol to remove any remaining water, refueled and flew the airplane home. Then he learned about the 1992 Cessna safety recommendation -- which he says he hadn't received earlier -- urging pilots to install additional fuel drains, and he did so. But afterward, on an April 5, 1999, flight, the airplane's engine stopped again, this time at 3,000 feet. Flying without power, he made another emergency landing, at Smyrna Airport.
Determined to see whether the plane was flawed, Mr. Scovill gathered a number of witnesses in his hangar in Murfreesboro, Tenn., for some tests. He poured a premeasured amount of water into his airplane's fuel tanks and performed the preflight procedures specified by Cessna. But not all of the water drained out.
Mr. Scovill then wrote to Craig Roberts, head of the FAA's Flight Standards District Office in Nashville, describing his repeated engine problems and the tests. The Cessna fuel system, Mr. Scovill said, is faulty, with a "consequent danger of crashing" that "is life-threatening."
Mr. Roberts and another FAA inspector, Paul Jones, performed the same water test on Mr. Scovill's airplane three months later and were unable to remove 13 ounces, even after shaking the wing. Mr. Roberts then wrote supervisors in Washington, calling for a "review of the water/contamination egress capability of the Cessna integral fuel tank which includes all similar designs" to the 172P -- the model number of Mr. Scovill's plane.
Although the fuel tank is designed so that water will sink to the lowest point on the wing, where the drains are located, critics of the wet-wing design say structural ribs along the inside of the wing can keep water from reaching the drains. Most critics say the main problem is that the slope of the wings isn't steep enough to allow the water to flow to the drains. The typical dihedral, or slope, on a Cessna single-engine airplane is between one and two degrees, compared with four or five degrees on other single-engine aircraft, experts say.
The other leading single-engine aircraft manufacturers, the Raytheon Aircraft Co. unit of defense giant Raytheon Corp. , and Piper Aircraft Inc., don't advise their pilots to use the so-called rock-and-roll procedure.
The FAA in Washington sent details of the Tennessee water tests to Wichita, where the agency's single-engine certification office is based. Carlos Blacklock, then the head of the Wichita office, sent two inspectors to look at Mr. Scovill's plane.
They came back "with the conclusion that there is indeed water in the tank, and that it's hard to get it out," he says.
At about the same time, Robert Lee Cunningham, an FAA maintenance inspector in Orlando, Fla., was growing alarmed after a review he conducted at Embry-Riddle Aeronautical School in Daytona Beach, Fla. He turned up 83 pilot reports of problems in the schools' fleet of 58 Cessna Skyhawks, all wet-wing planes built after the 1996 manufacturing restart.
Mr. Cunningham wrote the school in January 2000, admonishing it about "repeat accounts of engine roughness and stoppage without conclusive corrective action," dating to the arrival of the first new Cessnas in the fall of 1997. He also says he advised Wichita the next month of his suspicion that water in the fuel tank was the source of the problem and urged the agency to order Cessna to correct the problem.
Embry-Riddle, the largest pilot school in the country and one of Cessna's biggest customers, asked the aircraft maker to fix the problem. Cessna eventually agreed to upgrade, without charge, all 58 of the planes, boosting their original 160-horsepower engines to 180-horsepower.
Embry-Riddle Chancellor Thomas J. Connolly says the engine hesitations have disappeared, and that tests performed at the school have shown water wasn't the issue. Neither Embry-Riddle nor Cessna say they can explain why the upgrade seemed to bring an end to the hesitations.
Filling the Tanks
But Mr. Cunningham says that with the horsepower upgrades, Embry-Riddle instructors are now able to fill their fuel tanks to the top, leaving less room for condensation buildup or water entrapment. The school had been operating the weaker-engine Cessnas with the fuel tanks half full in order to save weight and accommodate extra observers on student training flights.
After reviewing accident and service-difficulty reports on Cessna single-engine airplanes filed with the NTSB, Mr. Blacklock and the FAA team wrote Cessna on March 13, 2000, identifying an "unsafe condition" on Mr. Scovill's airplane and probably many more. "We believe this condition may exist on all Cessna high-wing integral-wing fuel-tank-equipped airplanes," he wrote. Cessna says that description fits more than 20,000 of its aircraft in the field.
Mr. Blacklock ordered Cessna to propose specific design changes to remedy the apparent fuel-tank flaws. For Mr. Scovill's model, the 172P, Mr. Blacklock demanded proposals within 30 days. He also ordered the manufacturer to submit a list of all the other planes that used a similar tank design and corresponding serial numbers for each airplane in service, as well as proposed design changes for them within two months.
On April 10, Cessna's Mr. O'Brien responded, rejecting any reason for concern. He cited a prior FAA audit of the wet-wing fuel tanks in new Cessnas that found they "met regulatory requirements and performed as intended." Without proposing any design changes, Mr. O'Brien said Cessna would "initiate a significant investigative program" to determine if the 172P fuel-tank design is flawed and provide details of the program "in the near future."
FAA officials were growing frustrated, internal agency documents show. On May 30, the FAA's top regional inspection officers sent the manufacturer a letter requesting a voluntary halt to any shipments of single-engine aircraft from the new plant in Independence. Cessna officials say they were taken aback by the action. "It certainly got their attention," says John Hickey, the FAA's head of certification in Washington.
Cessna complied with the request. But that day, the company flew six senior officials in a company jet to Kansas City, Mo., to meet with the FAA's top regional regulators. At that tense meeting, Cessna provided agency officials with its own research into Cessna flying-safety records and persuaded the agency to limit the scope of its inquiry, according to people familiar with the matter. The FAA agreed to allow shipments to continue after just a one-day stoppage.
In a special hangar at Cessna's manufacturing facility in Wichita, FAA officials and company representatives are testing Cessna Skyhawk models 172R and 172S made after 1996. They are doing it much in the same way Mr. Scovill did -- introducing water and then seeing if the recommended draining procedure gets it all out. The 172Rs and 172Ss represent the bulk of Cessna's current single-engine production. FAA officials say the tests are being widened to other models to include the 172P, Mr. Scovill's older model.
Jeffrey Janusz, a former Cessna engineer who is heading the FAA's investigation, says there is a lot of tension between the agency and Cessna in Wichita. "Things have just gotten too heated up around here," he says. He says he is trying to reach a conclusive result that will resolve the matter. "I'm hoping to have a bulletproof case, whether it be good news or bad news," he says.
Write to Jerry Guidera at jerry.guidera@wsj.com

Corrections & Amplifications:
The February 1986 crash of a Cessna airplane near Elyria, Ohio, didn't take the life of Scott Marx, as incorrectly reported in the above article. The article also incorrectly states that Mr. Marx, who lives in Wakeman, Ohio, piloted the plane and that three other passengers were hurt in the crash. Mr. Marx's father, Dwyane Marx, was the pilot and was killed in the crash, which injured two others.
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby 170C » Wed Jan 10, 2018 6:19 pm

Robert Scovill hangars his C-172P in the same bldg that I do. His hangar ajoins mine at the nw corner, but in back of my hangar. I have met him only once when I walked by his open hangar and he and an employee were working on one of those coin machines that allows one to wash your automobile at a self service car wash, at least that was what I think it went to. I introduced myself and complimented him on his pristine 172 sitting in the hangar. He proceeded to give me a 20 minute talk about water in Cessna fuel tanks. He showed me 8-10 different Cessna fuel tanks with portions of the top cut out of each. In the bottom of these tanks there were stains of various sizes and locations which he said were due to water sitting on the bottom of the tanks. His theory is that, as the article George posted said, that all of the water that may be in a Cessna fuel tank cannot be removed via the sump drains and that resulted in his several forced landings. He told me about trying to convince Cessna of the flaw in their design with no apparent success other than the newer 172's having 13 sumps instead of the 3 most of us are acquainted with on our 170's/172's. He told me his 172 has approximately 1000 hours since new, but he won't sell it due to his concern about his liability.
I have talked to numerous aircraft owners here at MBT (Murfreesboro, TN) that have had the same conversations with Mr Scovill. Some, like me, didn't put a lot of credence or concern into the subject because most of us haven't experienced engine roughness or failure due to water in the fuel. However, apparently it isn't all that rare. Visiting recently with the head of maintenance for Middle Tennessee State University's aviation fleet, I was told he believes there is a potential problem with the design of some Cessna fuel tanks based on some tests he observed with Mr Scovill. There seems to be a theory that no AD or Service Letters have come from Cessna, other than rocking the wings during preflights, is that Cessna's lawyers and corporate funding may have kept the problem swept under the rug! The gentleman commented that he would not expect any action from Cessna unless or until some high profile entertainer or like person is critically injured or is killed and it can be traced back to the water in the fuel tank issue. He knows I fly a '56 172 with a tail wheel and his comment was that due to the location of the sump drain and the angle of the tanks with a tailwheel Cessna that he felt there was much less of a potential problem. Interesting what we find out about our planes!
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby gahorn » Wed Jan 10, 2018 6:47 pm

I had an exciting experience with a mid-60's C182 which belonged to an A&P in DAL. He ran his airplane using mogas and had a 55-gal drum and pump in the bed of his pickup and bought his fuel at local gas stations.
One day he and I (pax) took off on Rwy 13L at Love Field and at approx 100' AGL the engine died. We landed on the remaining runway and coasted clear of it and onto the ramp.
After examining the fuel we found considerable water in the fuel and an entire day was spent draining fuel from the airplane and his re-fueling system. I never felt confident that we'd gotten rid of it all.
His airpalne was typically moored outdoors in weather, and his refueling system was in an open PU bed, exposed to wx. The mogas sometimes/often contained ethanol. His fuel tanks had rubber bladders. It was a bad set-up all-around, IMO.

He drained at least 20 gallons of that contaminated gasoline into an open sewer on the ramp. :?

(This guy's judgment was defective in several ways... He later attempted to cheat another of our Members out of his recently-overhauled instruments by substitution during a panel-rebuild. We discovered the ruse when I noticed the equipment list had recorded the instrument serial numbers. (Hint: Serial numbers of all your installed equipment and avionics, and engine accys is always a good idea.)

About 3 years ago one of our Members called me to see if I knew any FAA MX inspectors in the DFW area because he was receiving interference from one of them in not approving a ferry permit to move a retract-gear airplane by flying it gear down to a place where repairs could be made. Turns out that when he mentioned the FAA Inspector "stuttered badly"... I recognized the name... Yep... he's now FUZZ in the Dallas area. :roll:

I've added a drain to my fuel selector valve but have never found water there.

Keep your tanks full in storage, and keep your airplane indoors out of the rain, and/or cover the fuel-caps and never use mogas with ethanol. IMO
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby ghostflyer » Thu Jan 11, 2018 5:01 am

While I do not want a law suit filed against me or others , but a number of years ago when this hot bed of half truths and deceptions were going on ,[ Note... a meeting with the FAA was held with Australian stake holders which wasn’t about Cessna and the water in the fuel situation but about rules and regulations harmization in each country ]. I had the privilege of sitting down with the upper echelon of the FAA and later some of the senior staff of Cessna . But the hot topic of the day was discussed . Certain trends or actions were noted when aircraft owners complained about water in their fuel tanks . Some of the owners were flogging a dead horse for notoriety and hoping for some other gain [ maybe money]. I gained the impression the knowledgeable FAA personal knew what the issues were but had to present it in a political correct format.
The aero club that I was flying with at the time had a number of 172P,s . We have a hot humid climate and plenty of afternoon storms.
There was never a real fuel issue with water , yes a water drain was carried after refuelling and sometimes a table spoon was drained out. Even today after the who haa has died down , these aircraft still do not have real water issues .
Even with my own aircraft I do water checks before each flight and still have had no issues.
I am curious ,does Mr Schofield still fly his aircraft . ???
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby 170C » Thu Jan 11, 2018 2:58 pm

He does not.
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby hilltop170 » Thu Jan 11, 2018 8:21 pm

If proper filtering is done before fuel is put in the tanks and you keep the tanks full, there probably won't be a water problem.

I had a 75 gal tank built for the back of my pickup that I have used since 1985. It has a 12v. pump with 20' hose, a water/sediment cartridge filter, and a water go-no go filter downstream of the sediment filter.

Until leaded mogas was outlawed that is all that was ever put in the tank and since then filtered 100LL from the jobber in Anchorage is what I have used. I have never had water in the sediment filter bowl or in my plane tanks, and the go-no go filter has never shut off flow. I have replaced both filter elements when recommended.

I have had the same results with the metal tanks in the 170 and bladder tanks in the 180.

All bets are off if you keep your plane tanks partially filled or fill from cans.
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby n2582d » Thu Jan 11, 2018 9:32 pm

Water can get into an airplane's tank accidentally in a number of ways, including condensation released from the fuel under rapid outside temperature changes ...
I've never heard of this. How rapid does the temperature change have to be?

Belite has a fuel-water discriminator for $1000. Not STCed, PMAed, or TSOed but I bet it wouldn't be too hard to obtain a field approval for such a device on a certified aircraft given the FAA's concern on the issue of water in the fuel. I would want some sort of a test function for the unit. Otherwise how would you know if the "presence of water" function is working? I'll be buying one right after I get a BRS parachute for my plane. :)
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby cessna170bdriver » Thu Jan 11, 2018 9:54 pm

It would be interesting to see the rib design in those Cessna wet-wing tanks. In Van's RV's (at least the -4, -6, -7, and -8 models), the fuel tank ribs have a slot designed into the lower aft corner for the express purpose of allowing water (and fuel) to easily drain from bay to bay. I'm unaware of any problems with water getting trapped in those tanks.
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby gahorn » Thu Jan 11, 2018 10:55 pm

n2582d wrote:
Water can get into an airplane's tank accidentally in a number of ways, including condensation released from the fuel under rapid outside temperature changes ...
I've never heard of this. How rapid does the temperature change have to be?
...]


It's easier than you might think. .. cruising at 7500' it's possible to have 35 degrees difference from S.L. easy... and burning up 25 or 30 gals of fuel allows that much volume of humid air to enter the tanks. Descending back down ... your chilled airframe may condense water against the interior walls of the tanks and run down into the fuel. In fact, that's a very common reason you often find a teaspoon of water in your tanks next day. The fuel sloshes around and keeps it stirred up until it settles out... or hopefully is captured in your gascolator.
Warmer climates make it worse. The most I ever found was after a flight to the Bahamas and back years ago. Both planes in the flight of two actually had bladder tanks but lots of water found in them next day.
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby n2582d » Thu Jan 11, 2018 11:51 pm

George, I get water condensing from the air in the tank but the quote gave me the impression that water is being formed from the fuel itself.
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Re: WSJ 04/30/2001 Cessna Fuel System

Postby gahorn » Fri Jan 12, 2018 2:52 pm

n2582d wrote:George, I get water condensing from the air in the tank but the quote gave me the impression that water is being formed from the fuel itself.


I knew... you knew. :wink: I used your post didactically for those who visit the Forums and may not. :twisted:
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