Debate With the Devil

I leaned the mixture again and again ... and the gauges kept racing downward

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A Piper PA28-181 Archer crashed in night IMC approximately two miles from its destination airport, killing the pilot and passenger. The aircraft was destroyed. The instrument rated commercial pilot had approximately 300 hours total time, including 70 hours actual or simulated IMC and 90 hours in the accident aircraft. Witnesses reported hearing the engine begin to run roughly then go silent followed by the sound of impact a few moments later. FAA investigators drained less than one gallon of fuel from the left wing tank and found only trace amounts of fuel in the right tank. Fuel starvation was listed as the cause of the accident.

I have read dozens of accident reports similar the one above and always ask myself the question: How could a competent pilot be so (choose one: careless, reckless, stupid, unthinking) to run out of fuel? Its simply a matter of fundamental fuel management: How much, including reserves, do you need for the flight? How much do you have?

If you do not or will not have enough then plan for a fueling stop. Sounds simple. Well, I was less than five minutes from being the pilot in the fictional accident report above.

I consider myself to be extremely conservative, if not paranoid, when it comes to safety. I make safety lessons learned notes to myself after every flight, practice at least once a week, fly different aircraft out of different airports around the country, fly with different CFIs, and have even walked away after a preflight because I just didnt feel right about the flight. Heres how a competent, safety conscious pilot can be so (fill in the blank) to nearly run out of fuel.

It was a December Sunday that was perfect for instrument flying. Ceilings ranged from 300 to 1,500, cloud tops from 7,000 to 10,000; freezing level above 8,000; winds aloft out of the southwest at 23 to 27 knots. Light turbulence and no convective activity in the forecast.

I filed plans for my home airport in New Jersey to New Bedford, Mass., and return. My alternate for the return flight was approximately 30 miles northeast of my home airport. I planned a 65% Best Economy setting out (7.6 gph) and 75% Best Economy back (8.8 gph). Based on 48 gallons usable, I had enough fuel to make the round trip, fly to my alternate and have 1:46 in reserve – well above the 45-minute IFR requirement. In the preflight, I noted that the left tank was full to overflowing and the right tank down perhaps an inch. Both fuel gauges registered slightly below the full mark. Fuel was not a problem.

On the flight out, we spent half of our time in the clouds and the rest skipping on the cloud tops at 7,000. Winds aloft were slightly higher than forecast at 33 to 35 knots but all other conditions were as forecast. Wheels up at 17:59Z and touchdown at 19:40Z. Planned fuel burn was 11.4 gallons and, as far as I could tell from the fuel gauges, we had burned about that (right gauge showing 20 gallons and left showing 15 gallons – remember, at full, both were indicating below the Full line). Ground control directed us to parking, within yards of the fuel pumps, and we were off for an afternoon of touring.

The briefing for the return flight was a little troubling. Ceilings were forecast to be 200 feet broken at home and winds aloft had increased to 30 to 32 knots directly off our nose. A quick recalculation of fuel burn still indicated a reserve of more than an hour after flying the missed approach and diverting to the alternate. I was comfortable with an hour reserve for a 2:20 flight. So it was wheels up at 01:45Z.

The first sign of trouble was our ground speed – ranging from 70 to 85 knots. A quick calculation of winds aloft at our cruising altitude of 4,000 indicated 43 knots from 255 – an average headwind component of nearly 40 knots. Still, I figured we had enough fuel for the trip, including IFR reserves. The second sign of trouble was the fuel gauges; they seemed to be racing toward Empty. I leaned the mixture again and again; double-checked that our throttle setting was for 75%; introduced carb heat – and the gauges kept racing downward.

Heres where I began my debate with the Devil: Either believe the gauges (fuel starvation before getting home) or believe my calculations (enough fuel including IFR reserves). The Devils evidence went something like this: Your fuel burn out was as calculated – how could you possibly burn 11 gallons out and 37 on the return trip? The gauges are wrong!

The gauges both registered below full during preflight, when they were clearly full to the brim. The gauges are wrong! Piper would never design a fuel gauge that actually is empty when it says Empty – imagine the lawsuits brought by poor mourning widows. The gauges are wrong!

Remember what the POH said: Endurance is 4.8 hours PLUS a 45 minute reserve at 75% power. Time en route will only be 4 hours when when we get home. Range with reserves under the same conditions is shown at 560 miles – were only flying 404 miles. The gauges are wrong! Youve flown this plane on dozens of trips and have never experienced the fuel burn indicated by the gauges. Even if you assume 75% Best Power (10.5 gph) for the entire flight you would only burn 42 gallons. Even the example calculation in the POH uses 7.6 gph for fuel consumption. The gauges are wrong!

The Devil won the argument.

We continued home, flying within a few miles of our alternate. (Me: What if the gauges are right? Why take a chance? Lets just divert to the alternate and get this thing on the ground. The Devil: Its 10:30 at night. You wont be able to fuel up. Think of the inconvenience; your wife will have to drive 45 minutes to pick you up; another 45 minute trip in the morning during rush hour – probably be an hour and a half. What about the poor guy who has the plane reserved in the morning? Youre only 15 minutes from home and its all downhill. Cmon, the fuel burn rates in the POH are based on maximum weight – youre hundreds of pounds below that. Youd be causing all that inconvenience for nothing. The gauges are wrong!)

The Devil won again.

Our descent took us directly over the airport enroute to the VOR for the full VOR approach. ASOS reported ceilings at 800 feet and winds out of the South at 10 to 12 knots. As we approached the airport from the northeast, I thought about getting below the clouds and scud running for a left base entry to runway 12 and forgetting about the VOR approach.

But what if ASOS was wrong about the ceilings? Also, engine failure at 700 agl didnt leave many options. The VOR was only four miles from the airport. Id have a better chance using my handheld GPS to navigate following engine failure at 2,000. The Devil lost this argument. I decided on the full VOR 8, circle to land 12.

We broke out at 800; off the nose was the most welcomed rotating beacon I had ever seen. Keyed the mic and on came the runway lights. Fuel switched on right tank for our left turn; maintained altitude and kept it tight – just in case; power-off approach. I have never felt such relief as when we touched down and taxied up to parking.

First thing the next morning, I called the FBO to find out how much fuel was needed to fill the Archer. The shocking answer: 47.5 gallons out of forty-eight usable. We had one half gallon of fuel – not even enough to do the missed approach let alone fly to the alternate. We were minutes from being the victims in the accident report above. The Devil almost had his way!

How could we possibly have burned that much fuel? I dont know but here are my guesses: The right tank was not topped off, the power setting was higher than indicated, carburetor ice present, fuel octane low, or engine/aircraft condition caused performance to differ from the POH. It was probably a little of each, but I believe the real demon was leaning. An obscure sentence in Section 5 of the POH reads Endurance can be grossly affected by improper leaning procedures. What if my leaning wasnt perfect? For example, if we flew four hours at 11 gph plus two gallons for taxi and run-up and, say, 1.5 gallons below full in the right tank at take-off and, guess what: 47.5 to fill the Archer!

So what did I put in my Lessons Learned log for this flight?

1. Believe the instruments. We have it pounded into us during instrument training but usually think in terms of attitude indicator, VSI, DG, bank/turn coordinator, etc. It applies just as critically to the fuel gauge: Believe the gauges, not your own senses. The only time you should let your senses prevail is when they say you have less fuel than indicated by the fuel gauges.

2. Dont listen to any of the Devils arguments. If you have any doubt, get the bird on the ground as soon as possible. I should have advised ATC of our situation and asked for a diversion to an airport for refueling. A little inconvenience (or even a major one) is far better than the grief your loved ones will feel when they get that call from the authorities.

3. Dont blindly rely on performance data in the POH. Differences among aircraft, fuel, flying habits, and leaning procedures of the PIC can grossly affect fuel burn and other performance data.

4. Refuel, even if you dont believe fuel to be a problem. This could have all been prevented if I had simply refueled at New Bedford before starting the return flight – remember we parked a few short yards from the fuel pumps.

I feel very fortunate to have survived this experience and will carry its lessons with me for the rest of my flying career. I hope that by sharing this experience, others can benefit from the lessons without having to live through the terror of believing that you may only have minutes before engine failure in night IMC.

———-

Wind Provides Icy Reception
It was a beautiful calm day. Wind 230 at 4 according to ATIS on the phone. I really should be doing other things but I was struggling with the winter weather and holiday currency issue and needed to grab a few turns around the pattern whenever possible. I headed for the airport.

There was no ATIS on the radio. Well, they were probably in between. As I began to taxi and tested the brakes, the nose on the 172 seemed to go way down; farther than I remembered. I looked out, the wings appeared to have a negative angle of attack so I shut down and got out to look. The strut appeared to be at the right height. The plane was on rough icy buildup. So, I lit her off again.

As I taxied through the tiedowns, the rudder pedals felt odd, as if the rudder trim was set fully to one side. I stopped and ran the trim lever back and forth a couple of times and centered it. After that, it didnt feel familiar but it seemed all right.

I picked up ATIS in the 29 runup area. Wind 230 at 4. Notice of icy patches on 36. I checked in with the tower with Uniform since I hadnt told anyone I had the numbers yet. The tower gave me the wind anyway 240 at 4 and cleared me for 29.

As the plane began to roll, the nosewheel began a terrific shimmy. Shimmy is something you have to put up with in hard working school planes but this was the worst I had experienced. I pulled the nose up to lighten the wheel and the plane began to lift off well below flying speed in the dense air and ground effect but, the shimmy didnt stop. I began to lose directional stability and skate sideways. There suddenly seemed to be a lot of cross wind. It flashed through my mind that I did not want to be up in the air with a rising crosswind, a hinkey nose wheel, and the proper runway possibly out of service. I pulled the power, got the plane under control, and turned off. Still, it was as close as I have ever come in my 100 hours to losing control of an airplane.

As I taxied back, I noticed the windsock. It was straight out and I could feel the wind buffeting the plane slightly. Then it hit me. The wind was ONE FOUR.

I hadnt put in crosswind correction anywhere near sufficient for the conditions. Sure, the shimmy damper is punky, but the cross loads and the rising upwind wing were making everything much worse. I was so predisposed to hearing four from the phone and recent radio ATIS that, when the tower said one four my brain skipped right over it. I was also preoccupied with the nosewheel issue.

Lesson: Listen and, if something unusual is going on, pay extra attention to the usual; you are apt to miss a small but vital issue. I should have realized that, if they were giving me wind immediately after I told them I had Uniform, something must have changed.

Still, Im glad I didnt wind up in the air rusty; with a stiff rising crosswind, a badly shimmying nosewheel, and ice on the other runway. Takeoffs are like landings, if they dont feel right, abort.

———-

Wheely, Wheely Exciting Landing
I was flying a rented Dakota on the first leg of a 10-day vacation to Canada.I had done a thorough (I thought) preflight, loaded my three passengers on board and off we went. Our first leg was from my central California base to southern Oregon.

The 2-hour flight was uneventful. After a smooth touchdown I began having trouble holding centerline as the airplane drifted left. I added right rudder and got back to the center, only to have the drift start again.

I decided to go around, added power, and watched as the drift got very severe. When it became obvious that I would leave the runway, I pulled the throttle and hung on.

We did a 180 across the dirt and taxiways. We were lucky – no damage done.I found that the left main tire had been flat-spotted through to the cord by a previous renter and it blew out on touchdown.

Since then I always roll the airplane and inspect all the tires through 360 degrees before flying.

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