King Air Pilots Should Look at Their Fuel Caps Before Takeoff

[pelmet]

Flew with an old-timer on the King Air years back who gave me some advice to always check the fuel caps on the nacelles for a leak after the props were had been taken out of feather. Turned out he knew what he was talking about as I was being positioned on a flight in a Beech 99 a few months later and I saw a bunch of fuel coming out of one of the caps as we taxied out. Cap had to be replaced in that case due to a faulty seal but in this case, it was simply not having the cap on properly.

"C-GDFF, a Beechcraft C90A aircraft operated by Moncton Flight College, was conducting a local training flight from Fredericton Intl, NB (CYFC). Shortly after departure, the crew noted fuel leaking from the left wing filler cap and requested to return to CYFC via radar vectors. The crew declared an emergency and landed at CYFC without further incident. The operator's maintenance determined that the fuel filler cap was not installed correctly after refueling."

[Victory]

Moncton Flight College has King Airs?

[PostmasterGeneral]

Yeah. It’s to give the Chinese kids some “two Crew turbine” experience before they head home to fly a 777.

[kevenv]

2 at YFC. They are flying pretty much non stop, mostly round robins in the FIR but some to YQB and back as well.

[ahramin]

I don't get this post. Isn't it on the walkaround that you check fuel caps? And don't you do that for every aircraft?

[pelmet]

I don't get this post. Isn't it on the walkaround that you check fuel caps? And don't you do that for every aircraft?

gave me some advice to always check the fuel caps on the nacelles for a leak after the props were had been taken out of feather.

On the walkaround, the fuel caps are checked for proper installation. After engine start once the props are out of feather, the nacelle fuel caps are checked for leaks. These are in the airflow from the props which seems to create a lower pressure(Bernoulli stuff) and suck fuel out of the cap if not properly installed and functional.

So, no I don't do it for every aircraft(although I'm sure it couldn't hurt to do so) because most aircraft don't have the fuel cap in the airflow from the engine and therefore there is no more likelihood for fuel to be sucked out of the cap once the engine is operating. This means that an improperly installed, or in my case faulty cap, wouldn't start leaking until once airborne. For fuel caps out of the engine airflow that are visible from the cockpit, aside from checking for proper installation on the walk-around, the best time to check for a leak would be soon after takeoff.

Keep in mind that from the report, one cannot be sure of which fuel cap was leaking. It may not have been a nacelle tank cap. I just thought I might pass on some good info from an old-timer.

[goingnowherefast]

Older king airs with the nacelle tanks, isn't that tank slightly pressurized when the engine is running? Something to do with jet transfer pump in the center section tanks? Been a while since I've flown one. I can see that the prop wash would cause a visible fuel spray, instead of just burbling out of the cap and hard to notice.

I'm not talking about the 350s with the STC'd extended range tanks in the nacelles.

[pelmet]

Beech fuel caps are not the best in my opinion. Here is some good info on Baron and Bonanza fuel caps and suggestions for preventing leaks from chains getting caught or when to be more suspicious than normal after a rain event based on water or lack of water pooled behind the locking tab.

http://www.csobeech.com/fuel-caps.html

[all_ramped_up]

I had my VHF on and heard this incident go down live. They waited awhile to declare an emergency which wasn't until they were a few minutes away from touchdown.

Whomever was working the radio had mentioned a fuel leak, then later when it became a fuel imbalance they called in the emergency.

I don't wrench on King Airs so I can't comment on the rest of it.

[pelmet]

C-GMRS, a Beech B200 aircraft operated by PAL Aerospace Ltd., was conducting flight SPR01
from St. John's (CYYT), NL to St. Anthony (CYAY), NL. After departure, the flight crew noticed fuel
leaking from the left wing fuel filler cap, and coordinated with air traffic services for a return to
CYYT. The crew requested airport emergency services stand by, and made an overweight landing
without further incident.
The CYYT airport initially closed all runways, and later limited the closures to runway 11/29, 02/20
and taxiway Bravo, which were closed for approximately 2 hours to allow spilled fuel to be cleaned
up. An aircraft had its landing delayed, and 2 aircraft had their departures delayed due to runway
closures.
Company maintenance personnel inspected and tested the fuel cap and filler mount, and noted no
defect. An overweight landing inspection was carried out. The company is further investigating the
occurrence.

[co-joe]

Heard a second hand story of a King Air out of YXD having a fuel cap pop out after takeoff, and as the story went the medics pointed out the massive fuel leak, so the crew joined a circuit and landed immediately. They say the tank was basically empty by the time they taxi'd in. Pretty powerful vacuum lift is.