I have had the absolute privilege of owning N29HL, a Cessna 172M, for right at one year. In that year, she has taken my family and me from our home base at 5R4 (Foley, Alabama) to Oklahoma for a family Christmas, New Orleans for business and pleasure, Jacksonville to visit friends, Auburn for football games, and many places in between, logging about 150 hours over that time. My five-year old daughter’s favorite place to visit, however, is Dauphin Island, identifier 4R9, a short 24 NM flight along one of the prettiest beaches in the world, to a secluded island runway with our “private beach” and crabs by the thousands for the catching.
Two facts are of particular importance for this story. First, I am blessed to co-own 9HL with a wonderful friend and mentor who owns a flight school, and uses the plane for instruction whenever I’m not flying her. Second, I have checked the oil in this plane so many times I couldn’t begin to count. In recounting this, I hope to not only tell the story, but give a glimpse into what was happening in real-time as the evening unfolded.
This Saturday evening began like so many. “Daddy, can we go fly to Dauphin Island for a daddy-daughter date?” my five-year old asks. After a quick check of the weather (the usual summer afternoon CN’s popping up, bases about 3500 feet, the proverbial weather prediction of scattered thunderstorms, and plenty of room to fly well around them) I get permission from the boss (mom) and give the go-ahead. We get to the airport at 5 pm, and she helps me pre-flight the plane.
A check of the maintenance logs showed that the plane had just had a 50-hour oil-change and had not been flown since. On preflight the dipstick showed eight quarts of oil. No other squawks on pre-flight, run-up complete, one lap around the pattern for good measure, and we were off across the bay to a carrier-style landing (ok, as close as I’ll ever get anyways) at Dauphin Island. Squeaked the wheels down, secured the plane, and we were off for fun.
As the sun began its slow descent, we headed back to the plane for our homeward leg. This was where things got interesting. Convincing the five-year old to leave the beach with all the crabs to catch and pretty shells to collect was not a quick business, and I underestimated the amount of time needed to get back to the plane in full light.
The sun was low on the horizon as we got to the plane, and the idea of a takeoff over the water after sundown was low on my list of fun things to do with a tired/hungry kid in the right seat.
In years past I would have skipped the full pre-flight, knowing that no one had touched the plane, and that I just completed a thorough inspection two hours before and flew only a 30-minute flight. I’ve become a bit of a safety nut in the last year though (thanks in large part to achieving my instrument rating), so I overcame the urge to launch and did my standard walk-around.
Everything was normal until I got to the oil (always my last step in a well-defined process). When I pulled out the dipstick, I could read every tick mark down to the two-quart mark, in shiny silver. I grabbed a rag from the plane, wiped it down, stuck it back in, pulled it back out, and checked again. Still no oil to be found. I looked over at the sun and saw it resting on the water, sinking by the second. I again wiped the dipstick, stuck it back in, screwed it down this time, and then reversed course and carefully inspected it under the flashlight that I have the five-year old bring from the plane. Nothing.
I simply couldn’t believe it. The plane ran fine all the way over. I always do a gauge check, including temps and pressures, as I enter the pattern (old habit from flying a Cherokee where “gas on the fullest tank” meant something), and I didn’t recall anything being awry as we landed. Had I simply overlooked this due to expectation bias? Was I so lucky that I had dumped all my oil, but had not overheated or damaged the engine due to the short flight?
I got behind the rear seats to grab a quart of oil and put it in, just to see if it would register. Maybe I could add enough to get us back home? A check of the cargo area revealed that someone had used the quart I always keep in the plane, and not replaced it. Being such a short flight, I didn’t bother to check for spare oil, especially with eight quarts in the case!
I cursed myself for this seemingly simple oversight as my mind started to race. Can I make the flight home? Do I call someone to come get us? By car or by air? Bed time was coming, we hadn’t eaten dinner, and daylight was quickly fading. Further, Dauphin Island’s runway sits over the water, making any night landings a perfect setup for a black-hole effect NTSB story.
On the other hand, the 24NM direct flight equates to an hour and 45-minute drive one-way by car due to geography. Even with these factors, I quickly ruled out making the flight. No matter what route I took, a short portion (or long if I went direct) would put me over the water, at twilight. While an engine-out scenario would never be fun, these factors would seem to make it lethal, especially with my five-year old on board.
I called my flight instructor, friend, and mentor, who teaches out of the school I co-own the plane with. He graciously dropped what he was doing and headed to the home airport to grab another plane and come be our knight in shining armor. I then called my co-owner, who owns the flight school, and filled him in on the situation. “Where did the oil go?” he asked. Hmm, that’s a great question, I thought.
While on the phone, I began to look the plane over in earnest. The 172M model, like many others, has only the oil-hatch door on the cowling, so a good look inside isn’t really possible on the ramp. Nothing down the sides. Laying on my back, I saw a slight film over the bottom of the plane, and shining a light on the front fork revealed a small amount of oil. “Aha!” I exclaimed. Likely the result of a loose oil filter, or possibly a leaking sump I astutely diagnosed. Funny that there was no oil in the hangar when I got the plane out…
After securing the plane on the tie-downs for the night, our evening concluded with an hour wait on the runway (that was fun with a five-year old), a night takeoff from Dauphin Island back home in a different plane than the one we arrived in, and very late night for all involved. Safety wins again!
So why was this the emergency that wasn’t? The easy and first answer was a thorough pre-flight revealed a potentially serious safety condition that could have been fatal had it been ignored or skipped. The real reason, however, is a bit more embarrassing. The chief mechanic from the flight school flew over the next morning to diagnose the problem and fix it so the plane could be brought home. When he pulled the dipstick, there were just over seven quarts of oil in the case.
As it turns out, the brand new oil, once heated on our flight to the island, had turned as translucent as water on the shiny silver dipstick. Inspecting the dipstick while looking towards the setting sun across the cowling made it virtually impossible to see the oil, and far easier to see the markings than usual. In checking the oil hundreds of times before flights, both right after and far away from an oil change, I have never seen oil like this. I even went to the ramp after the plane was brought home to see it again for myself, sure that there was another explanation.
In the end, I had to hang my head, take some good-natured ribbing, and swallow what little pride I had left. But what about the oil I saw on the fork and belly? It turned out the oil I had seen on the fork was a small amount that had spilled during the oil-change and didn’t get cleaned up because a storm sent the mechanics and line-crew running to get planes inside immediately after a run-up and leak check was performed on my plane, and to the best of my assumption this spill must have sprayed a light sheen down the belly of the plane on our flight, giving me confirmation that I indeed had no oil in the crankcase.
I made my sincere apologies to those affected by my blunder, and scampered away from the field with my head hung low to process. In doing so, there were a number of take-aways from the experience that I would like to pass on.
- Never, EVER, skip your pre-flight. You never know what can change, even on a short flight or with no one else touching the plane since you landed last. Had there really been no oil in the plane, and had I rushed past this to get off the ground before twilight, we could have had a complete engine failure over water or very desolate land. While I have mentally prepared for a ditching or forced landing, and practice the latter regularly, doing it for real with my five-year old on board is something I pray to never encounter.
- Get-home-itis is real. We’ve all read the stories and NTSB reports, so this sounds like a “DUH” kind of statement, but here is how it affected me. I had to make myself believe that I didn’t have oil in the plane (ironic really, but in the moment, that was my reality). I checked the dipstick three times not because I thought there really was sufficient oil and it would show up, but simply because I couldn’t believe that there was no oil in the engine.
- Aviation is a wonderful and small community, and I’m never alone. I didn’t want to call in someone to come get my daughter and me because it would affect their schedule (and admittedly, I still feel bad about this). However, no one affected was upset, and all validated my decision to not fly the plane given what I thought I knew. Was I let off scott-free? Of course not. We’re too good of friends for that. But I was encouraged to make that decision every single time. I was also encouraged to go get my eyes checked before flying again.
I told my daughter all of this, from the problem with not having oil that night, to finding out that there was actually oil the whole time. Her response: “Daddy, you had oil the whole time! You’re so silly. We could have flown home in Hotel Lima!” Five minutes later, after we’d moved on to other things she quieted down and then said: “Daddy, thank you for keeping us safe, even if you are silly.”
She thinks I made the right decision. Do you?