NTSB Factual Report

HISTORY OF FLIGHT

On December 26, 2005, about 2030 central standard time, a twin-engine Piper PA-31-350, N711HG, operated by Midwest Aviation, sustained substantial damage on impact with terrain while approaching the Southwest Minnesota Regional Airport - Marshall/Ryan Field (MML), near Marshall, Minnesota, during a forced landing following an in-flight loss of engine power from both engines. The non-scheduled domestic passenger repositioning flight was operating under 14 Code of Federal Regulations Part 91. Night instrument meteorological conditions prevailed at the time of the accident. The flight was conducted on an activated flight plan. The pilot sustained minor injuries and was hospitalized for observation. The flight originated from the Guymon Municipal Airport, near Guymon, Oklahoma, about 1730.

The pilot's accident report, in part, stated:

Checked weather in Guymon OK (KGUY) for Marshall MN

(KMML) and Sioux Falls SD (KFSD) prior to launching Part 91

reposition flight. Metar for KMML indicated at or above ILS

[instrument landing system] minimums at KMML. Services at

KGUY were for fuel and no oil.

Launched VFR from KGUY, filed airborne and received amended

IFR clearance, which included direct to Hill City KS VOR (HLC)

then direct KMML. Had tailwind at altitude and 15 [percent] higher

ground speed on repositioning leg than on previous leg. Leaned to

Peak EGT [exhaust gas temperature].

Approximately 100 nm [nautical miles] S of KMML, noticed both

fuel gauges indicated a faster fuel burn than expected at peak EGT. In

my previous flights in the aircraft make/model, I had not seen the fuel

gauges move that quickly at any given power setting. Checked weather

at KFSD and was below minimums for ILS. Checked weather at

KMML and was above ILS minimum. Fuel gauges indicated would

have enough to continue flight to KMML, shoot ILS and land.

20 nm SW KMML, right fuel boost pump annunciator lighted and the

right engine began to sputter. Switched right tank from main to aux

tank and restarted engine. However, it did not run smoothly and

cycled from high power to almost off. Right and Left fuel gauges

indicated approximately 19 gallons remaining in each aux tank and 20

gallons remaining in each main tank.

Contacted approach and requested ILS 12 KMML, indicating Bingo

fuel and received several vectors outside the LOM [locator outer

marker] at KMML.

The right engine failed again, cycled the right fuel selector back to the

right main tank and kept both right/left boost pumps on. I attempted

this cycling once more (right main tank to aux) along with rocking

the wings in order to slosh any remaining fuel into the feed system or

dislodge an obstruction which may be preventing the engine from

getting the fuel remaining in the tank(s).

Approximately 30 seconds later, the left fuel boost pump annunciator

lighted and left engine failed. Switched left fuel selector to left aux

tank and was able to restart the left engine momentarily.

I did not feather the engines as they both were cycling from full power

to idle and as yet still able to produce some power.

Approximately 1 minute later, both engines failed and the aircraft began

to lose airspeed and altitude quickly as I was attempting to make it clear

to ATC [air traffic control] that the vectors outside the LOM were too

far and did not have the time or altitude to begin the approach several

miles outside the LOM. I again, switched both tanks from aux to main

and attempted restart.

Shortly thereafter I heard a radio call; "Good luck Hotel Golf".

Noticed airspeed and altitude were low and could not see the airport or

anything on ground due to night and overcast conditions. Switched on

taxi lights in an attempt to illuminate landing area. Saw what appeared

in the windscreen to be a large bush come up out of the pitch black

darkness and surmised that ground impact was imminent. Pulled aft

elevator in order to use remaining airspeed to establish a nose-high

landing pitch attitude.

The aircraft struck in a belly-first attitude, rolling forward toward the

nose, turning slightly to the left, and then bouncing airborne. I pulled

hard aft on elevator in an attempt to prevent the nose from hitting first

and the aircraft bounced again on the belly then rolling forward for a

second time. Prior to the third impact, I released the control wheel so

as not to break my wrists should the aircraft strike the ground in such

a manner as to jar the control wheel.

The aircraft settled after the third bounce and slid along ground to a

stop while yawing to the left. To minimize the potential for fire, I

switched off fuel, electrical and magnetos.

PERSONNEL INFORMATION

The pilot held a commercial pilot certificate with ratings for single and multi-engine land airplane, single engine seaplane, and instrument airplane. The pilot also held a flight instructor certificate with a rating for single engine airplane and instrument airplane. The pilot reported that he had accumulated 1,868 hours of total flight time and 42 hours of flight time in the same make and model as the accident airplane. He reported that he had accumulated 453 hours in night conditions and 152 hours in actual instrument conditions. The pilot's first class medical certificate was issued on July 11, 2005, with a limitation for corrective lenses. The pilot reported that his last flight review was on April 1, 2005.

AIRCRAFT INFORMATION

N711HG, a 1981-model Piper PA-31-350, Chieftain, serial number 31-8052110, was a low cantilever wing, twin-engine semimonocoque design airplane, with a retractable landing gear. The airplane was powered by two, turbocharged, direct-drive, air-cooled, horizontally-opposed, fuel-injected, six-cylinder engines. The left engine was a Lycoming TIO-540-J2BD engine (serial number RL-11149-51A) and the right engine was a Lycoming LTIO-540-J2BD engine (serial number L-1811-68A), both rated at 350 horsepower.

Billing receipts showed that 65.9 gallons was purchased for the airplane at GUY. The pilot's fueling request was that the outboard tanks were to be refueled.

The airplane's pilot operating handbook and airplane flight manual, in part, stated:

The fuel system consists of fuel cells, engine-driven and emergency

fuel pumps, fuel boost pumps, control valves, fuel filters, fuel

pressure and fuel flow gauges, fuel drains and non-icing NACA fuel

tank vents ... . ...

Fuel is stored in four flexible fuel cells, two in each wing panel. The

outboard cells hold 40 U.S. gallons each, and the inboard cells hold

56 U.S. gallons each, giving a total of 192 gallons, of which 182

gallons are usable. Fuel is routed from the fuel cells to the selector

valve, the fuel filter, the fuel boost pump, the emergency fuel pump,

the firewall shutoff, the engine-driven fuel pump, to the injector, then

to the cylinders. The fuel selector, filter, fuel boost pump, emergency

fuel pump and firewall shutoff are located on the butt-rib of each

wing panel.

The emergency fuel pumps are installed for emergency use in case of

an engine-driven fuel pump failure. They are also used for takeoff and

landing and, when necessary, to prime the engines. Control switches

for the emergency fuel pumps are located in the overhead switch panel

to the right of the fuel gauges.

Two electric fuel-quantity gauges are mounted in the overhead switch

panel. The right fuel-quantity gauge indicates the quantity of fuel in

the selected right fuel system tank (right inboard or right outboard),

and the left fuel-quantity gauge indicates the quantity of fuel in the

selected left fuel system tank (left inboard or left outboard). The fuel

gauges are connected electrically to micro switches mounted in the

fuel selector console. The fuel senders are also connected

electrically to the micro switches. When a fuel tank is selected, its

corresponding micro switch is actuated, which completes the

circuit between the fuel senders and its fuel quantity gauge,

providing a visual reading of the fuel quantity in the selected tank.

The gauges are illuminated, and the lights are controlled by a

rheostat switch on the left side of the overhead switch panel.

The fuel boost pumps are operated continuously and are provided to

maintain fuel under pressure to the other fuel pumps, improving the

altitude performance of the fuel system. There are no fuel boost

pump control switches or pressure gauges provided. Each fuel boost

pump is controlled by a separate circuit breaker, located in the circuit

breaker control panel. The fuel boost pumps are activated when the

master switch is turned on and continue to operate until the master

switch is turned off or the fuel boost pump circuit breakers are pulled

(off). Fuel boost pump warning lights, mounted on the annunciator

panel, illuminate when the fuel boost pressure is less than 3 PSI. In a

full power continuous climb from takeoff to high altitude under

conditions of high ambient temperature, high climb rate, and

extremely volatile fuel, the boost pump may not maintain a sufficient

pressure head to the engine-driven fuel pump. This condition would

be indicated by engine fuel pressure fluctuations of 2-5 PSI and/or

illumination of the boost pump warning light. The pilot may continue

the climb by using the emergency fuel pump to provide steady fuel

pressure for the high power operation; the emergency pump can be

turned OFF after level-out if reduction to cruise power extinguishes

the boost pump warning light. Cruise can be continued with the

emergency fuel pump OFF if fuel pressure remains steady and above

34 PSI, as indicated on the engine fuel pressure gauge.

METEOROLOGICAL INFORMATION

At 2015, the recorded weather at MML was: Wind 210 degrees at 5 knots; visibility 4 statute miles; sky condition overcast 300 feet; temperature 0 degrees C; dew point -1 degree C; altimeter 29.68 inches of mercury.

At 2035, the recorded weather at MML was: Wind 260 degrees at 4 knots; visibility 3 statute miles; sky condition overcast 300 feet; temperature -1 degree C; dew point -2 degrees C; altimeter 29.68 inches of mercury.

At 2055, the recorded weather at MML was: Wind 200 degrees at 3 knots; visibility 2 statute miles; sky condition overcast 200 feet; temperature -1 degree C; dew point -2 degrees C; altimeter 29.67 inches of mercury.

WRECKAGE AND IMPACT INFORMATION

The airplane came to rest upright in a snow-covered field about five miles west of MML. Examination by a Federal Aviation Administration Inspector revealed that the airplane's fuel tanks exhibited no fuel. No pre-impact anomalies were detected with the airplane.

ADDITIONAL DATA/INFORMATION

The FAA was a party to the investigation.

Federal Aviation Regulation Part 91.167, Fuel requirements for flight in IFR conditions, in part, stated:

(a) No person may operate a civil aircraft in IFR conditions unless

it carries enough fuel (considering weather reports and forecasts and

weather conditions) to-

(1) Complete the flight to the first airport of intended landing;

(2) Except as provided in paragraph (b) of this section, fly from that

airport to the alternate airport; and

(3) Fly after that for 45 minutes at normal cruising speed or, for

helicopters, fly after that for 30 minutes at normal cruising speed.

(b) Paragraph (a)(2) of this section does not apply if:

(1) Part 97 of this chapter prescribes a standard instrument approach

procedure to, or a special instrument approach procedure has been

issued by the Administrator to the operator for, the first airport of

intended landing; and

(2) Appropriate weather reports or weather forecasts, or a

combination of them, indicate the following:

(i) For aircraft other than helicopters. For at least 1 hour before and

for 1 hour after the estimated time of arrival, the ceiling will be at least

2,000 feet above the airport elevation and the visibility will be at least

3 statute miles.

NTSB Probable Cause

A loss of engine power in both engines while on approach due to fuel exhaustion and the pilot's inaccurate fuel consumption calculations leading to him refueling the outboard tanks only.