On Borrowed Time

It was a hot, bright Galveston Saturday. Under the supervision of my A&P, I had spent the day under his hangar door and the upper cowl door of my Cheetah replacing the baffling on the pilot’s side of the airplane’s engine bay. The job had taken all day. I was proud of what I had done, and I was also dehydrated and tired and still had to fly the plane back to Pearland. That was a short twenty minute hop that shouldn’t be a problem.

My A&P, Bill, inspected the job I had done, replaced a spark plug lead wire I had moved to avoid damaging, and declared the airplane airworthy and ready to fly back. Calling my wife in my iPhone, I told her I was about to leave and asked her to meet me at Pearland’s airport in about twenty minutes. Grabbing the airplane’s prop right at the hub, I pushed the airplane out into the bright sun and back about twenty feet before turning it ninety degrees, pointing the tail at the large, empty expanse of concrete ramp behind me. Then, I walked back into the hangar to get my headset which had been borrowed by astronaut Garrett Reisman so he and his wife, Simone, could work on the intercom in their Grumman Tiger. They thanked me for letting them use it, and I headed back with it and boarded my airplane.

I strapped myself in and ran through the pre-start checklist, yelled the obligatory “Clear Prop!” and started the Cheetah’s engine. I held the brakes as I flipped the beacon and radios on and listened to Galveston’s ASOS, setting the altimeter. I decided to go ahead and do my pre-takeoff checklist before taxi, so I performed it, in I then switched my second comm. radio up to the frequency for Pearland’s AWOS and flipped my primary comm. radio over to Galveston Ground. As I did, the pilot of a V-tailed Bonanza near the fuel pumps called for taxi. Ground cleared him to taxi to runway 17 via taxiway Echo, and I saw the tip of his vertical tail sharking its way out from the rows of airplanes to my left. I was closer to 17 than he was and thought about trying to get out ahead of he guy but decided to be courteous and wait. So, I delayed my call for taxi until the Bonanza was almost past. Unfortunately, the Bonanza pilot did not return my favor; in fact, he stopped in the middle of the taxiway between me and runway 17 and spun ninety degrees, blocking the taxiway, to do his pre-takeoff checks. I waited for a minute or two for him to clear; and when I had had enough, I called Ground and asked for permission to taxi in front of the Bonanza. The controller replied that the Bonanza pilot had just called Tower for takeoff as I saw the airplane start to move out. Switching up to Tower, I called for takeoff and Tower told me to hold short for the Bonanza, which I rogered and did. The V-tail roared down the runway; and as it lifted off, the tower cleared me for takeoff but said there would be someone on left base behind me. I pushed the throttle up and rolled for the runway, kicking left rudder to turn me left and align me with it. As the nose swung to the centerline, I advanced the throttle and the engine sputtered! I pulled the throttle back to idle and decided to try one more time since I had plenty of runway left and advanced it again. This time, it worked as expected. Roaring down the runway, I pulled back on the yoke at 60 and lifted off. All my engine instruments looked good and the airplane was climbing fine, so I asked for a right turn to the northwest from the tower at three hundred feet and got it. As I rolled right, the Tower asked me to take interval on the Bonanza also heading northwest. Spotting him, I called “tally ho!” and rolled out on my heading which was about thirty degrees more northward than his.

The Cheetah was climbing at about 700 fpm, a good rate for a still hot day, and I leveled off at 1600 feet MSL as I approached Tiki Island. The engine coughed once again, and I switched individually to the Left and Right magnetos to look for a problem. They seemed fine. I switched my comm. radio to the frequency for Houston Approach South and listened to the controller vector traffic as I otherwise non-eventfully cruised toward Pearland. I watched the oil temperature slowly creep up; the baffling job I had done had helped us out some but still seemed to be impacting the bottom line little. I looked forward to rebuilding the other side to see what effect the overall rework would have.

At about five miles out from Pearland, I switched the radio up to Pearland’s CTAF, pulled the power back to 2200 RPM, and began a descent at about 125 mph toward the field which was in sight. I could see no one else in the pattern and at about three miles I called my entry toward the left downwind leg of runway one four. That’s when all hell broke lose; the engine began sputtering and backfiring! SH*T!!!! It was only a matter of time before the engine quit.

With my heart in my throat, I leveled off at a thousand feet (pattern altitude) but let the speed bleed back on its own rather than forcing a slowdown. I decided not to touch the throttle in the hopes that the engine would continue to run, however roughly, until I could get abeam my landing point. I remember looking down about a third of the way down the runway with an uncertainty of how I would land it from there if the engine gave out, and I kept whispering to myself “Come on! Come on!” as we made our way alongside the runway. I hit the half-way point and ran down the landing checklist and, abeam my landing point, pulled the throttle back to idle. I decided to fly a simulated engine out approach from there rather than hang any hope the engine would continue, even though I was fairly sure it would be there.

I turned base at about eight hundred feet and as I slid perpendicular to the runway, turned toward it. I was holding best-glide, 83 mph, and intended to keep it there until I knew I had the runway made. Feeling I was high, I lowered the flaps down full as I turned onto a short final. But as I ran in toward the runway, I could see I was coming up a bit short, I lowered the nose twice to push my landing point more toward the runway but at about three hundred feet felt I needed to retract the flaps to get there for sure. The airplane sank like a stone but I did round out and touch down a couple of hundred feet past the threshold, much too close to the end for the scenario I had.

As I rolled out, I pulled the canopy open to get some cooling air in the airplane and I coasted to a stop on taxiway Bravo. Once clear of the runway’s hold short lines, I performed the post-landing checklist and then, with brakes locked, advanced the throttle up toward 1800 RPM. As the RPM approached it, the engine began backfiring and sputtering, and then quit, dropping 300 rpm, before starting again and repeating the surging. I swapped mags to see if I could isolate the problem, but I couldn’t. I taxied the airplane over to its parking spot in front of its little carport and shut it down.

Whipping out my iPhone, I called my mechanic and told him how the engine had misbehaved and that I was not sure whether I was going to have an engine for landing or not. We had been chasing this problem as either an ignition or carburetion problem, but I was convinced it was something else, i.e., a sticking intake or exhaust valve, and my bet was on the latter. I told Bill the Cheetah was “hard down” until he came up and looked at it, though what I really meant was it was “hard down” until we had a definitive cause we had fixed. Bill said he expected to be up my way next week.

I called my wife next. I had expected her to already be here but figured it was for the best she wasn’t. There was no way if she had been she would not have heard my problematic engine, and she’d have been freaking out until I was on the ground. When I got her on the line, I found out she was still at home; so, I asked her to bring me a Coke. I needed something to drink. I sat down in the shade of the “carport” to cool off for about ten minutes, then got up to park the airplane.

Pulling the towbar out of the airplane’s baggage compartment, I snapped it into shape and then onto the Cheetah’s nose. I turned the airplane about two hundred degrees until her tail was pointed straight back into her parking place and pushed her back into place as my wife pulled up. Once the airplane was spotted, I released the towbar and stowed it back in the baggage compartment and sat down with a Coke to get some liquid in my system. I’d finish tying down the airplane later.

I didn’t speak for a few minutes. Once I had some fluid in me, I told my wife the tale of the troublesome flight. For once, I said, I was glad she hadn’t been with me; we both agreed if she had she might never fly again. I told her about my conversation with Bill and what the implications of fixing a valve might be. In any case, it was pretty certain the airplane was going to be down a good, long while.

A few minutes later, when both shade and drink had cooled me, I got up and finished securing the airplane. As we drove back, she said she was happy I was all right and her eyes teared up and I said I was glad I was okay, too.

On Monday morning at work, I told a friend of mine who is also a CFI about the ordeal. I had been mentally evaluating what had happened ever since and knew I could have done better if I had thought it out. First, I had decided that if I had to do it over again I would have declared an emergency on 122.8 to ensure that any aircraft that might have been in the traffic pattern I didn’t see knew to steer clear of the approach end of runway 14. By not doing so, I had minimized my difficulty, which didn’t seem so bad because it had happened within an easy gliding range of the airport. But what if someone I hadn’t seen had hit final before me and I had to perform a go-around. Would I have been confident the engine would have been there for me? I knew the answer was “No!”. Secondly, during the interval when I only had about a third of the runway beside me and had the engine quit, I had several options. One was a quick left turn and a spiral down to the opposite end of the runway. Another was to continue straight ahead until I had lost only another two hundred feet and then perform a spiral turn back to land on 14 at the middle of the runway. Both solutions were reminders not to get “padlocked” on a single solution, i.e., touching down in the nominal landing zone on the runway I wanted. The winds were calm and landing in either direction would have worked just as well.

Hurricane Dolly just pushed ashore today south of here, and the change in the weather has all but guaranteed it will be another week before the Cheetah gets looked at. In any case, any kind of valve problem means I’ve been flying on borrowed time, and the Cheetah won’t be flying again until it gets fixed.

Miracles Happen but in Airplanes They're Called UA's.

I had planned to help my wife work around the house; but the engagement of one of my sons and his desire to hook up with us that night via iChat made an unscheduled trip to the beauty salon necessary for her. Suddenly, faced with no obligations, I decided to go back down to Galveston where my infirm Cheetah sat. I had said to my mechanic when I had left the night before we needed to run the airplane on the right mag alone to verify our analysis of the problems it was having. So, I decided to do just that, taking my flight bag with all my flight gear inside it. I hopped into my truck and headed south on that hot and sunny day toward the beach and the wide, towered airfield that was Scholes Field.

When I got there, after making my obligatory stop at the Terminal to hit the restroom, my airplane was sitting at the mouth of Bill’s hangar as if he had known I was coming. Bill, one of his interns, and probably the pilot of the Mooney they were working on were behind my airplane, huddled around the Mooney’s engine. Bill was threading a wire past its cylinders and seemed oblivious to my presence; I decided just to press on with getting the airplane ready to pull out of the hangar. As I checked out the cockpit, Bill came up and said hello and attached a tow bar to the airplane’s nose and we pulled the airplane out about twenty feet and turned it so the tail was pointing at the wide expanse of concrete behind me.

“You watch,” I said to Bill, “this darned airplane will check out just fine. What are we going to do then?”

Bill shrugged his shoulders.

“Go fly it?” he supposed. We were leaping off into the world of “Checks good on deck: cannot duplicate the problem” also known in NASA-speak as the “Unexplained Anomaly” or “U.A.”.

I laughed, hopping in the cockpit and rigging up my headset while grabbing my checklist and strapping in.

“Clear prop!” I yelled, after running through the pre-start checklist, giving the engine three shots of primer because it hadn’t been run much. I switched the Mags to Left and hit the Starter button. The prop cranked over a couple of times and I pulled the throttle full back and the engine roared to life. Her oil pressure was already on its way to the green as soon as I checked, so I brought the radios up and then checked the engine gauges again. Everything looked great.

I placed the Run-Up checklist on my lap and pushed the throttle forward, the engine following me up to 1800 RPM’s as I did. My feet mashed on the airplane’s brakes and she bucked against standing still; the wind was trying hard to blow off my hat not protected by the open canopy. I switched the Mags to Left and watched the RPM drop down about 125 and sit there. I switched them back to Both and they bounced back to 1800 and then dropped 125 again as I switched to Right. The damn thing had done what I had jokingly suggested; it had run like nothing had ever been wrong with it!
I taxied the airplane around in a loop just to give me something fun to do; and when I got the nose pointed back around again, I stopped the airplane, locked the brakes, ran her up to 1800 RPM, and checked the mags again. And, again, they passed!
By now, Bill was glancing at me from inside the hangar. Laughing, I have him a “thumbs up”. As he walked toward me, I shut the airplane down and hopped out.

“Do you believe that?” I asked.”

“Of course,” he said, “it’s an airplane!”

An airplane engine and its environs is the hottest about twenty minutes after it’s shutdown. I wanted to see if the problem we were looking for might be heat-associated, so I told Bill I’d let it heat-soak for 20 minutes and then restart it and try it again. I also decided that if it passed that mag check, I had no good reason not to take it flying. Bill agreed. I got on my iPhone to call my wife and we talked about the plan for the afternoon, which had just shifted due to a now-flyable airplane. She offered to cancel her hair saloon’s appointment about thirty minutes away, but I told her there was no need. For one thing, until I flew the airplane a bit, I really didn’t know if it was indeed “up” or if I needed to return it to the shop. My test plan was to fly it to Pearland, where I would do two touch and go’s and then land and check the magnetos. If they performed normally, I then would have the option of flying some more or pulling the airplane over into the shade of our covered tie-down and awaiting her there. If they didn’t and I trusted the airplane enough to get it back to Galveston, I’d be flying it back to where my truck was and wouldn’t need to fetch it back. She went on to her appointment with her hair stylist, and I went on to my appointment with the airplane.

I performed a complete pre-flight as Bill called the Evergreen FBO to inquire about the status of the fuel pump which has been down almost as much as my Cheetah this year. When they told him it was indeed broken, he asked them to drive the fuel truck down, and they agreed. I found a couple of inspection plates missing from the bottom of the right wing where Bill had been working and called out to him. He had overlooked them, and he finished buttoning them down as the fuel truck arrived. I asked the fuel truck driver to top off both wings. He said “Sure” and then got busy with his task. I finished the preflight and came back around the front of the airplane to find him finishing up and ready for me to pay. I have him a credit card that he processed and then I signed for the gas, turned, and saw that his truck’s grounding wire was still attached to my airplane. I told him to “hold up” as I detached it and then he reeled it back.

Hopping into the cockpit, I pulled out a Houston area terminal chart and put it up against the windscreen if I needed it for reference, strapped in and strapped my kneeboard to my right leg. Down the Pre-Start Checklist I went, priming the engine only once to make it ready to start.

“Clear prop!” I called, as I made sure no one was in front of me to get hit. I pressed the Starter button, the propeller spun clockwise, and the engine came to life. Ignition to Both and Oil Pressure was up. Leaving the intercom off, I brought the radios on and listened to the current Galveston weather that could have been summed up by “clear and HOT!” instead of by temperature and altimeter. Setting the altimeter, I noted the winds as I watched my KLN-89B GPS spin out error messages I hadn’t seen before. Months of sitting in a hangar had apparently killed its internal battery and perhaps more, though in a few moments it did have a correct bearing and distance to Pearland.

I decided to do my Before Takeoff checklist before I called Galveston Ground, so I ran the engine up and did the mag checks and everything worked like it was supposed to. I configured the airplane and radios for flight and then called Ground who gave me a clearance to taxi to runway 17 using taxiway Echo, an instruction that put the takeoff runway only yards away. Closing the canopy as I taxied up to the hold short line, I switched over to Tower for clearance for takeoff and got it right away. Spinning left to align the airplane with the runway, I pushed the throttle in all the way and we surged forward. At 60 mph, I pulled the stick back to what I use as takeoff attitude, and after staying there for only a moment, the airplane lifted off. As it climbed and the remaining runway slowly disappeared under the nose, I glanced at the engine instruments and they all looked okay. I hit four hundred feet above the ground and requested a right turn from the Tower which they approved, so I cranked her around to the right until I was heading back up to the northwest toward Pearland across the small waterway that was the Intercoastal.

Below me, the homes on Tiki Island formed a circle to protect themselves against the water surrounding them, while slightly off to my right and ahead the oil tanks and towers of a petroleum plant marked the southern edge of the coastline north of Galveston. I leveled the airplane off at 1600 feet and switched my radio over to Houston Approach to listen for any air traffic that might be coming my way. The oil temperature gauge was indicating in the green but, unfortunately, way over to the right as it had been doing since we installed the PowerFlow.

I had about ten miles of visibility due to haze, but it was still a glorious day. I was flying again! I had forgotten how much I loved it and often it seemed that the struggles we were going through to keep an airplane and ourselves airborne in it weren’t worth it. But, at that moment, despite the hot running engine and the peeling paint, I was grateful to have an airplane of my own and grateful we could fly. Tomorrow might be another story.

As I approached Pearland, I listened to its automated weather broadcast and set up for runway 14 due to small but persistent southern winds. I was the only one in the landing pattern, so I did two touch and go landings as planned and then rolled to a stop on the third. Once I was clear of the runway, I pulled the airplane over in a convenient spot, ran the engine up to 1800 rpm, ad checked the mags again. They were fine. Not knowing how much longer it would be before my wife got there, I taxied the airplane back to the covered tie-down spot she hadn’t seen in months and tied her down there in its shade.

It’s been about a week since we’ve gotten her back, and I’m pleased to say the fuel leak in the right wing does look like it’s been cured and the mags haven’t misbehaved. The GPS is going to need some service and I’m going to have to chase the hot running engine, but at least we can fly now and then.

Like they say, miracles happen; just when it comes to airplanes, don’t expect them to last.

Problems, Problems, Problems...

I haven’t blogged for a while due to a combination of things; and one of those has been continuing mechanical problems with the Cheetah. For a few weeks, I had thought we were catching up with her and then I made the “mistake” of trying to get ahead of the performance curve by adding a PowerFlow exhaust to the engine. That was when all hell broke loose, some of which had nothing to do with the PowerFlow and the other part of which we’re trying to understand and figure out whether the PF had anything to do with it.

The major bugaboo has been the right fuel tank leak that developed. I caught it during a preflight month’s ago. The Cheetah, like all Grumman singles, has a wet wing that contains gas by using a sealant. Sometime in a Grumman’s life, you can expect the tank to start leaking and the sealant to need replacing. Well, this became our time, though the presence of two spatulas left in from previous attempts and now retrieved from our wing indicates that the airplane has suffered from this problem before. (The logs are down at my mechanic’s shop so I can’t check them to see when this was a previous problem.) Bill’s on his fifth attempt to solve the problem, though to his credit he’s only charging us for one. His son-in-law, Robby, an Aircraft Inspector, indicated to me that this kind of trail and error was par-for-the-course when repairing fuel tank leaks. A Traveler owner down at Galveston just dealt with the same problem, though he managed to get his fixed on the fourth attempt. It’s frustrating ordeal for all of us, me because of the months of flying time I’m losing and Bill because of the money he’s losing. We believe we have it fixed wth this fifth attempt. I hope so. I just topped that tank of and with av-gas over $5 per gallon, it’s going to be an expensive test if we’re wrong.
I wish that was all that has been going on, but it’s not. Two things manifested itself with the installation of the PowerFlow exhaust system. Both mags began “popping” during the mag checks, and the left mag will often “surge” (drop 300-400 rpm and then recover and repeat it again) when the engine is run on the left mag alone. At first we thought it was a common heat-related failure induced the mag, but we saw it with a cold engine after changing out to a “new” mag. We have checked the switch, the wires, and the plugs using testers and can’t find a problem. Bill and I are both suspicious of the ignition switch, but there is also the possibility that the PF has uncorked a more serious problem with the engine.

Secondly, for the one or two short flights I have been able to make after we installed the PowerFlow, the engine oil temperatures have shot up to the high side of the green. It looks like this was induced by the PF system, and there was an article in the AYA Star (the Grumman owner’ group newsletter) that unfortunately appeared after I had installed the PF and discussed just a such an induced problem with the system in Tigers. Right now, though, with the mag drop problem we’re experiencing, I can’t say anything for sure about the cause. Once we get the engine operating correctly, then I’ll take a look at the oil temp and decide where to go from here. The article suggested opening more exit area at the bottom of the cowling, something I would do only after reworking my baffles and resealing every air escape hole in the top of the cowling I can find.