Many of the entries in my stack of pilot log books make reference to being a “maintenance check flight”. The vast majority of those were utterly routine. A few involved more exotic procedures, like engine shut-down and restarts at various altitudes and / or speeds. And yes, there was a time or two when the re-start failed, resulting in an “engine inoperative” landing. Though you wouldn't know it from the social and entertainment media of the US of A, such isn't any kind of real emergency so long as a) the inoperative engine isn't the only one installed, and b) the remaining engine(s) don't quit for the same reason as the first. (Think “running out of gas”.)
Once in a rare while something unexpected would pop up. Test flying a Cheyenne with a window removed for photo work resulted in a blast of air coming from the emergency gear extension access;
unexpected but non-threatening. A different Cheyenne had a pressurization hose come loose right around 18,000 feet resulting in a really rapid decompression. Unexpected, only slightly threatening for the first few seconds, and very loud.
Two “maintenance test flights” fell into a completely different category of threatening. One was a #2 engine failure (starboard to a sailor) on a small, twin engine Baron just as the gear left a narrow, not very long, runway that faced a hill. I did the things pilots need to do in such a situation, scraped over the hill getting a pretty good look at someone mowing their lawn. (They got a good look at me as well). As soon as the hill was cleared the emergency part of the flight was over, and yet another “engine inoperative landing” entry was made in my log.
The second was the test flight of an ultra-light that had already been crashed once. The cause of the crash was still a mystery. The pilot flying had suffered both a broken shoulder and a concussion during the event and remembered nothing of that whole day, resulting in him being of little help in figuring out what went wrong. The rebuilt craft had been carefully inspected by several people, including me, and nothing seemed amiss. Still, taking it on the maiden voyage after the rebuild might not have been the smartest thing I ever did; that thought flashed through my mind as the machine leaped into the sky in an impossibly steep, near stall attitude that I was unable to correct even with full nose down elevator. Had I been wearing a parachute that day I would have certainly used it to join the caterpillar club. Getting down in one piece involved some scary flying, monkey-bar antics to shift some weight, likely used up at least two of my extra lives, and still makes me wince when I think of it.
Which is the long way around of saying I take test operations very, very seriously. They are never spur of the moment, always well planned, with much thought given to what might go wrong and what to do in response. So when the word came down yesterday that we were going to “sea trial” the boat I have been working on, well, lets just say I was less than enthusiastic about the idea.
The boat isn't near done. There is no floor over the cockpit leaving batteries and other electrical equipment totally exposed. There are no covers over the engines, no hatch in the forward bow, and no windows in the cabin. There is no helm seat or rail, just a foot or so of standing space keeping the person at the helm from falling onto either one of the two exposed engines, or the exposed fuel tank. There is no VHF radio or navigation equipment. My pilot-trained paranoia envisioned a stern-heavy boat shipping water aft, shorting out everything important, with me swimming home with my butt hanging below the frame tubes of an ultra-light trying to shift the center of gravity (cg) forward.
The lift straps went limp and the boat settled into the water nearly perfectly on its lines; no evidence of being stern heavy at all. There was the slightest list to starboard which, given that nearly all of the 4/0 cable in the boat runs up the starboard side of the bilge, wasn't a surprise. We let it sit there for a half hour or so making sure the bilge stayed dry, which it did. With nothing stopping the show the Yard Owner, the Engine Guy, and yours truly stepped aboard. Start and house batteries came on line without sparks or smoke and the big Cummings engines rumbled to life with little coaxing; loud though, without covers. All communications from then on was done by shouting. The bow thruster churned massive amounts of water and, in the cabin, could be heard growling even over the engine din. I think, if we had put that dude in the center of the hull, it would just shove the whole boat one way or the other without much effort. (Wouldn't that make docking easy?)
We eased out of the lift pit and into the Manatee river. A few minutes later we were howling along at near full song, spray flying past the windows with (to a sail boat guy anyway) a massive wake chasing along behind us. The boat leaned port and starboard as the trim tabs got tested, another new thing to a sail boat guy. Sweeping turns didn't seem to upset the hull any and no spray came through the open windows. Even though the new props are not yet installed, robbing the boat of 150 RPM or so, top speed on a phone GPS app came in at 34 miles per hour. The engines ran smooth and sweet. (Still loud though.) The electrical system worked as planned. Engine Guy was happy. Yard Owner was happy.
I was glad my butt was dry.
Hopefully, soon, the wiring work will wind down. The bulk of the heavy wiring is done; bow thruster, windlass, inverter / charger, batteries and sundry switches, DC and AC breaker panel main power distribution panel, and a secondary distribution panel at the helm. There are still some lights, LPG gas control, and electronics to go. The stove isn't installed yet, nor is the refrigerator. The air conditioning has power but, for reasons yet to be determined, isn't running the fan at full speed or closing the compressor relay. The engine fire bottle lights are about half wired and I need to change the trickle charger line. (For some reason the paperwork calls for a 10 gauge wire on a 5 amp circuit, a puzzle yet to be solved.)
Still, it was fun to see much of the summer's work tested, and log my first real “sea trial”.
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| One of the many Cheyennes I did maintenance test flights on. |
unexpected but non-threatening. A different Cheyenne had a pressurization hose come loose right around 18,000 feet resulting in a really rapid decompression. Unexpected, only slightly threatening for the first few seconds, and very loud.
Two “maintenance test flights” fell into a completely different category of threatening. One was a #2 engine failure (starboard to a sailor) on a small, twin engine Baron just as the gear left a narrow, not very long, runway that faced a hill. I did the things pilots need to do in such a situation, scraped over the hill getting a pretty good look at someone mowing their lawn. (They got a good look at me as well). As soon as the hill was cleared the emergency part of the flight was over, and yet another “engine inoperative landing” entry was made in my log.
The second was the test flight of an ultra-light that had already been crashed once. The cause of the crash was still a mystery. The pilot flying had suffered both a broken shoulder and a concussion during the event and remembered nothing of that whole day, resulting in him being of little help in figuring out what went wrong. The rebuilt craft had been carefully inspected by several people, including me, and nothing seemed amiss. Still, taking it on the maiden voyage after the rebuild might not have been the smartest thing I ever did; that thought flashed through my mind as the machine leaped into the sky in an impossibly steep, near stall attitude that I was unable to correct even with full nose down elevator. Had I been wearing a parachute that day I would have certainly used it to join the caterpillar club. Getting down in one piece involved some scary flying, monkey-bar antics to shift some weight, likely used up at least two of my extra lives, and still makes me wince when I think of it.
Which is the long way around of saying I take test operations very, very seriously. They are never spur of the moment, always well planned, with much thought given to what might go wrong and what to do in response. So when the word came down yesterday that we were going to “sea trial” the boat I have been working on, well, lets just say I was less than enthusiastic about the idea.
 |
| The sea trial boat a few weeks ago |
The lift straps went limp and the boat settled into the water nearly perfectly on its lines; no evidence of being stern heavy at all. There was the slightest list to starboard which, given that nearly all of the 4/0 cable in the boat runs up the starboard side of the bilge, wasn't a surprise. We let it sit there for a half hour or so making sure the bilge stayed dry, which it did. With nothing stopping the show the Yard Owner, the Engine Guy, and yours truly stepped aboard. Start and house batteries came on line without sparks or smoke and the big Cummings engines rumbled to life with little coaxing; loud though, without covers. All communications from then on was done by shouting. The bow thruster churned massive amounts of water and, in the cabin, could be heard growling even over the engine din. I think, if we had put that dude in the center of the hull, it would just shove the whole boat one way or the other without much effort. (Wouldn't that make docking easy?)
We eased out of the lift pit and into the Manatee river. A few minutes later we were howling along at near full song, spray flying past the windows with (to a sail boat guy anyway) a massive wake chasing along behind us. The boat leaned port and starboard as the trim tabs got tested, another new thing to a sail boat guy. Sweeping turns didn't seem to upset the hull any and no spray came through the open windows. Even though the new props are not yet installed, robbing the boat of 150 RPM or so, top speed on a phone GPS app came in at 34 miles per hour. The engines ran smooth and sweet. (Still loud though.) The electrical system worked as planned. Engine Guy was happy. Yard Owner was happy.
I was glad my butt was dry.
Hopefully, soon, the wiring work will wind down. The bulk of the heavy wiring is done; bow thruster, windlass, inverter / charger, batteries and sundry switches, DC and AC breaker panel main power distribution panel, and a secondary distribution panel at the helm. There are still some lights, LPG gas control, and electronics to go. The stove isn't installed yet, nor is the refrigerator. The air conditioning has power but, for reasons yet to be determined, isn't running the fan at full speed or closing the compressor relay. The engine fire bottle lights are about half wired and I need to change the trickle charger line. (For some reason the paperwork calls for a 10 gauge wire on a 5 amp circuit, a puzzle yet to be solved.)
Still, it was fun to see much of the summer's work tested, and log my first real “sea trial”.
2 comments:
Sounds like you could have used a couple of old D&C headsets. :-)
Actually...
I thought about taking earplugs, then wished I had.
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