@Jim_R 's emergency thread inspired me to share. Unfortunately, my story is of how I didn't do what I should have, unlike his, but still a learning opportunity.
Took the Nanchang out yesterday and on taxi, I had my headset off and remarked to my copilot "I hear hissing". He agrees. This plane runs pretty much off air. Gear, flaps, brakes, ground steering, without air none of them work. The plane always sounds like a steam engine because every time you move something it bleeds off air, so you kinda get used to the noises, but I noticed enough of a difference to actually remark on it. I don't normally taxi without my headset, so I checked the air, and I had quite a bit more than minimum needed to take off and land again (and the normal amount under the conditions), so I continued on. Gear came up just fine.
Once flying, you don't really need air for anything until ready to land. But, during the flight I noticed we had lost air - which we should have been building it during the flight and not using any. I watched it close for awhile and increased rpms, checked all the controls to make sure the valves were seated, air held perfectly steady neither reducing or increasing, but it was about 40% lower than it would normally peak.
At that point, I decided to abort the flight, get back on the ground and diagnose. Gear down, flaps down, lost a bit of air, but still more than enough to brake safely and taxi home. Got home with about the same amount of air I hand on final.
Moral of the story is, Why in heavens name did I take off knowing something wasn't normal? I found excuses (not wearing headset) to dismiss an abnormal situation I should have taken more seriously.
To put it in perspective, there is an emergency tank still available that I didn't even need to leverage, but still this was a casual flight for recreation, stupid to plow forward when we both detected something wasn't right
With humility,
Salty
PS> Problem is already identified and resolved. Had a slow leak so that the compressor could just keep up with about 60% full volume, but couldn't go any further. This is why it wasn't going up or down.
Took the Nanchang out yesterday and on taxi, I had my headset off and remarked to my copilot "I hear hissing". He agrees. This plane runs pretty much off air. Gear, flaps, brakes, ground steering, without air none of them work. The plane always sounds like a steam engine because every time you move something it bleeds off air, so you kinda get used to the noises, but I noticed enough of a difference to actually remark on it. I don't normally taxi without my headset, so I checked the air, and I had quite a bit more than minimum needed to take off and land again (and the normal amount under the conditions), so I continued on. Gear came up just fine.
Once flying, you don't really need air for anything until ready to land. But, during the flight I noticed we had lost air - which we should have been building it during the flight and not using any. I watched it close for awhile and increased rpms, checked all the controls to make sure the valves were seated, air held perfectly steady neither reducing or increasing, but it was about 40% lower than it would normally peak.
At that point, I decided to abort the flight, get back on the ground and diagnose. Gear down, flaps down, lost a bit of air, but still more than enough to brake safely and taxi home. Got home with about the same amount of air I hand on final.
Moral of the story is, Why in heavens name did I take off knowing something wasn't normal? I found excuses (not wearing headset) to dismiss an abnormal situation I should have taken more seriously.
To put it in perspective, there is an emergency tank still available that I didn't even need to leverage, but still this was a casual flight for recreation, stupid to plow forward when we both detected something wasn't right
With humility,
Salty
PS> Problem is already identified and resolved. Had a slow leak so that the compressor could just keep up with about 60% full volume, but couldn't go any further. This is why it wasn't going up or down.
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