Setting The Selector
In some aircraft, you have to be a contortionist to see where the fuel-tank selector is pointing
If you've flown a variety of aircraft, you know that some designers decided to make it awfully difficult to see for sure which fuel tank or tanks you've selected. In some models, the fuel selector on the left sidewall may be easy to see while you're climbing over the right front seat on your way in. Once you're comfortable in the left seat, however, it may be impossible to see surface markings or even the selector handle itself without squirming around and leaning at an awkward angle. Aircraft with fuel selectors at floor level between or below seats may require minor in-flight gymnastics in order for you to be absolutely sure they're correctly positioned. There were two accidents in Florida that the NTSB recently finished investigating, which serve as reminders of how important it is to know something as basic as the direction the fuel selector is pointing.
Beech C23
At about 9:25 a.m. on February 25, 2010, at Gilbert Airport (GIF) in Winter Haven, Fla., the sky was clear, visibility was 10 miles, and the wind was from 330 degrees at 13 knots. A private pilot and passenger were planning to fly to Lakeland, Fla. The Beech C23 Sundowner they would be using was operated by a flight school located at the airport. The operator told investigators that the pilot was allowed to fly the airplane and only had to reimburse them for the fuel used.
A number of witnesses saw the pilot and passenger at the flight school before takeoff. The passenger was seen coming into the building and asking to borrow a fuel sampler. Another witness watched as the pilot checked the right fuel tank. The airplane was observed taxiing to runway 29. A witness reported that after its takeoff roll, the airplane lifted off normally. A witness who was outside near the departure end of the runway said the airplane had reached about 150 feet AGL in a normal-wings level climb attitude. Approximately five seconds later, after the airplane had reached about 200 to 300 feet AGL, the engine stopped. This witness, who was a pilot, stated that it was as if someone had pulled the mixture control back. The witness said the airplane pitched down about five degrees, as if someone were trying to build airspeed. It then banked to the right about 30 degrees.
The witness didn't think the nose was low enough to maintain airspeed. He knew the airplane was too low to turn and make it back. He said it appeared as if the airplane was flying slowly. He lost sight of it, and then heard the sounds of impact. He reported there was no sputtering and no smoke before the engine suddenly quit. Had it sputtered, he would have been able to hear that. He also said that he didn't see any parts separate from the airplane. After hearing the crash, he drove to the scene. When he arrived, sheriff's office personnel were already tending to the occupants.
Another pilot-rated witness, this one located at the flight school, had slightly different observations. He reported looking through a window and seeing the airplane nose-high, in a right bank estimated to be between 60 and 70 degrees. The witness then reported that the airplane began "dropping fast" to the right. He kept watching, but the airplane disappeared behind trees.
The airplane sustained substantial damage, and the certificated private pilot and the passenger were killed.
The airplane crashed about 6â10 of a mile beyond the runway, hitting a grass median between the lanes of a highway, then traveling across the two westbound lanes and coming to rest in a ditch.
Examination of the cockpit revealed the short end of the fuel selector handle that points to the tank selected was in the "off" range. During testing, no air could be blown through the valve when it was in the position in which it was found. The fuel-selector valve, handle, plastic shroud and guard were retained for further examination.
The pilot was 45 years old and held a private pilot certificate with an airplane single-engine land rating. His second class medical certificate was current. He had logged over 468 hours with 5.7 hours in the accident airplane.
Review of the maintenance records of the 1974 airplane revealed it had been signed off for an annual inspection on April 10, 2009, and a 100-hour inspection on August 12, 2009. The airplane total time at the time of the accident was approximately 6,003 hours. No record could be found of any maintenance involving the fuel selector valve. The manufacturer of the valve reported there's no required overhaul interval.
A pilot and mechanic who flew the accident airplane the day before reported that during their preflight the fuel tanks were within one inch of being full. They flew in the traffic pattern for only about a half-hour. They told investigators that flight was performed with the fuel selector positioned to the left tank, and it wasn't moved during or after the flight. A CFI with the operator visually looked into both fuel tanks before the accident flight departed, and noted the level of fuel in both was within two inches from the top of the tank.
An Airworthiness Directive from 1985 applicable to the accident airplane required modification of the fuel selector guard by installation of a "Selector Stop" and a decal with markings. Records indicated that the AD had been complied with during an annual inspection on December 13, 1985.
The fuel-selector valve has four detents, one each for the "left" and "right" positions, and two "off" positions. A one-piece handle attached to the fuel selector valve has a raised "arrow." The end of the handle with the raised arrow points to the desired fuel tank to supply fuel to the engine, or to one of the two "off" positions. The arrow is painted white, and the handle is painted red. A fuel-selector guard made of plastic surrounds the fuel-selector valve. The "selector stop" installed in accordance with the AD consisted of a stainless-steel spring to prevent inadvertent movement of the fuel selector to the "off" detent position. The fuel-selector guard did have three individual placards labeled "L Tank 26 Gal," "R Tank 26 Gal" and "off." The portion of the shroud beneath the lower edge of the fuel selector stop exhibited two green-line radial marks consistent with the positions of the left- and right-tank detents; however, the fuel-selector stop didn't exhibit continuation of either green line radial onto the full width of the stop, nor did the shroud exhibit continuation of the green-line radials above the upper edge of the stop. The shroud also didn't exhibit a red-line arc above the upper edge of the fuel selector stop between the green-line radials, nor did it have red arcs adjacent to the slots in the fuel selector guard.
The NTSB determined that the probable cause of this accident was the pilot's improper placement of the fuel-selector valve during takeoff, and his failure to maintain airspeed following a total loss of engine power resulting in an inadvertent stall. Contributing to the accident was the failure of maintenance personnel to detect the lack of proper markings on the fuel selector stop and fuel selector valve shroud at the last 100-hour inspection.
Piper PA-44-180
On November 11, 2010, at about 6:05 p.m., a Piper PA44-180 Seminole being operated as an instructional flight crashed following a failure of the left engine shortly after takeoff from runway 10R at the Palm Beach International Airport (PBI), West Palm Beach, Fla. A VFR flight plan had been filed for the nighttime flight. The flight instructor, a commercial pilot and two passengers were killed. There was a post-crash fire. The airplane was en route to Melbourne, Fla. (MLB). The FAA reported that a female voice, later determined to be the CFI, transmitted during initial climb that they had an engine failure and "needed to turn around and land."
The controller cleared the flight to land "any runway." The CFI had 2,278 hours with 492 in multi-engine airplanes. The commercial pilot receiving instruction had 298 hours with about 47 in multi-engine airplanes.
The four-seat, low-wing, retractable gear, twin-engine airplane was manufactured in 2008. It was powered by two 180 hp engines. A 100-hour inspection had been performed on October 25, 2010, at an airframe/engines total time of 1,638.3 hours.
Weather at the time was VFR with scattered clouds at 6,000 feet, winds from 200 degrees at nine knots, and visibility 10 miles.
The airplane impacted taxiway hotel (H) on the airport in a nose-down, right wing low attitude. Investigation revealed that the left engine was not operating at impact. Also, the left propeller was not in the "feathered" position as called for in the emergency procedures for dealing with engine failure. The left fuel selector was found in the "off" position, one inch aft of the forward stop, and the right fuel selector was found in the "on" position.
The NTSB determined that the probable cause of this accident was the failure of both the pilot and the flight instructor to ensure that the left fuel selector was in the "on" position for takeoff and their failure to follow proper procedures when the left engine lost power shortly after takeoff, resulting in an in-flight loss of control.
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