Engine Test on ground

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MattCe

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I have a friend who is involved in a aviation-related lawsuit. He has become deeply distrustful of one of the partners in the plane.

Aside from the obvious (not flying the plane), is there a way to safely test an engine on max power while on the ground? is it ok to run an engine (lycombing o-320) at max power, while stationary, so long as the CHTs don't exceed 400F?
 
I have a friend who is involved in a aviation-related lawsuit. He has become deeply distrustful of one of the partners in the plane.

Aside from the obvious (not flying the plane), is there a way to safely test an engine on max power while on the ground? is it ok to run an engine (lycombing o-320) at max power, while stationary, so long as the CHTs don't exceed 400F?
For how long? I often checked my engine at max power while stationary, but for only a minute or two. And is he worried that a partner has screwed up the engine? Very hard to prove who may have done it, even if so.
Choose your partners wisely. There are two people on the planet with whom I'd partner with on a large asset.
 
is there a way to safely test an engine on max power while on the ground?
Yes, but I recall there is a time limit. What do you hope to verify with a full power run up?
 
is there a way to safely test an engine on max power while on the ground? is it ok to run an engine (lycombing o-320) at max power, while stationary
What happens when you line up to take off? Is there a limit on how fast you need to be rolling before you open the throttle?
So, yea, you can give it the beans. Other than "it runs" or "it gets to the specified static RPM" would you learn? Either of these shouldn't take more than 10 seconds. Are you expecting to find something from an extended ground run?
 
The overhaul manual has instructions to test, but it does not tell us to run with it cowled, there is equipment installed to insure cooling.
other than that there is no specific instructions, you may see the pilots hand book.
 
Typical field overhaul run-in instructions prescribe ground runs including running to max power, followed by stepping down RPMs to allow cooling prior to shutdown.
 
I would slowly up the RPMs and pick a place with no gravel to get sucked up. I say this because many times the only place to do a full power runup out of the way of other planes is on little used gravelly pavement.


Tom
 
You can't get full power on the ground with a fixed-pitch prop. It won't reach anywhere near redline, which is where max power is made. You'll get a static RPM, and if it's in the range specified in the TCDS, the engine is producing appropriately.

The cowling is part of the cooling system in most airplanes. Running the engine hard and long with it off can cause local hot spots on the cylinders and heads, since the designed flow down between the cylinders isn't happening well at all. The CHTs might look OK, but that's no guarantee that everything's OK.
 
I have a friend who is involved in a aviation-related lawsuit. He has become deeply distrustful of one of the partners in the plane.

Aside from the obvious (not flying the plane), is there a way to safely test an engine on max power while on the ground? is it ok to run an engine (lycombing o-320) at max power, while stationary, so long as the CHTs don't exceed 400F?
I’m sure you’ve purposely made this ambiguous, but further details about what took place might be helpful.
 
full power run up on the ground....sure. No issues with a run-in engine.....and in fact it is needed to set some engine parameters.

Pick a spot with no gravel or loose sand....or you will damage the prop. Do not perform pro-longed ground runs or you could over heat the cylinders (CHT). But a full power run of a 15-20 seconds or so will not harm anything.
 
. Do not perform pro-longed ground runs or you could over heat the cylinders (CHT). But a full power run of a 15-20 seconds or so will not harm anything.
Yeah. that

I've seen cylinders cooked on the test set, but there is many factors to consider.
 
Yes, but I recall there is a time limit. What do you hope to verify with a full power run up?

He is hoping to verify that the engine makes continuous thrust without oil pressure or c/s prop rpm dropping. enough to get to pattern altitude. Like the other poster said, I'm being deliberately ambiguous for reasons I can't explain without giving too much away.
 
enough to get to pattern altitude.
FWIW: His idea is not very proactive. If there is a known oil pressure problem or even a slight anticipation of a possible oil pressure problem it would be best to verify the engine makes "book" oil pressures via a direct reading gauge and checked/signed off by a mechanic. Ambiguity or not, this isn't something to guess at unless you're being shot at.;)
 
I worked with a test pilot testing a new design for a while. His standard was he wanted to see a full power run up for 1 minute. He figured if it would run for 1 full minute at full power that would put him in a position he could glide back to the airport if necessary.

Brian
 
Any of you ever read an engine test cell report? My newest engine was run on a stand for 61 minutes. They start at 1500 rpm and ramp it up every 5 or 10 minutes. At the 42 minute mark it was run at full rated power for 15 minutes. The last 4 minutes were at idle to cool it down. Standard practice for engine test stands.

Here’s a Lycoming document about ground running. https://www.lycoming.com/sites/defa...ating engine Break-In and Oil Consumption.pdf
 
Any of you ever read an engine test cell report? My newest engine was run on a stand for 61 minutes. They start at 1500 rpm and ramp it up every 5 or 10 minutes. At the 42 minute mark it was run at full rated power for 15 minutes. The last 4 minutes were at idle to cool it down. Standard practice for engine test stands.

Here’s a Lycoming document about ground running. https://www.lycoming.com/sites/default/files/Lycoming Reciprocating engine Break-In and Oil Consumption.pdf
I bet the engine was tested IAW the Lycoming overhaul manual. and all the test equipment was installed. the test cell has a bunch equipment that as never meant to fly. Cowling is not designed cool on the ground, is designed to cool while flying.
 
There is a book that tells us to test an engine, Lycoming overhaul manual chapter 9 it lists the items required.. a test club Is required, as is calibrated gauges.
 
Read the link. Engine testing on the ground per Lycoming. My local engine shop has a similar set of instructions. Works great.
 
Any of you ever read an engine test cell report?
Yes and watched a few test runs. But as mentioned above test stand runs are night and day difference than running a fully cowled aircraft. For one they don't use any cowling instead use a special test "club" (prop) and a huge forced air cooling system to keep temps well below max levels. Plus some test stands can replicate various altitudes.
 
Yes and watched a few test runs. But as mentioned above test stand runs are night and day difference than running a fully cowled aircraft. For one they don't use any cowling instead use a special test "club" (prop) and a huge forced air cooling system to keep temps well below max levels. Plus some test stands can replicate various altitudes.
For Lycoming it is chapter 9 of the overhaul manual.
 
He is hoping to verify that the engine makes continuous thrust without oil pressure or c/s prop rpm dropping. enough to get to pattern altitude.
That's a long time time for a full power ground run without addressing cooling issues.
 
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