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J3Hetzer

I only just noticed.

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Posted (edited)

I might be tripping here but I swear the valve-springs and rockers used to move on the German engines (where they can be seen). Now they're static. Was it a RoF thing or are my marbles rolling?

Talking of engines, what's the ticking noise when the throttle's too far forward at lower alts?

Edited by J3Hetzer

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Posted (edited)
28 minutes ago, J3Hetzer said:

I might be tripping here but I swear the valve-springs and rockers used to move on the German engines (where they can be seen). Now they're static. Was it a RoF thing or are my marbles rolling?

 

You're flying the Halberstadt, apparently. Move your head to the side and you'll see them move. It's a slightly different engine block compared to the Albatros and Pfalz.

 

 

Quote

Talking of engines, what's the ticking noise when the throttle's too far forward at lower alts?

 

It's overcompression on the Mercedes D.IIIa, and it's only present on the Halberstadt CL.II 200hp, as the other planes don't have it (yet).

 

Technically speaking it's pre-ignition, a.k.a. "knock". The fuel/air mixture is overly compressed at lower altitudes meaning that it often spontaneously combusts due to engine heat and burns up unequally rather than at (or slightly before) TDC, when the piston reaches the spark plugs. This can damage the cylinders over time. In other words: don't use full throttle at low altitude.

Edited by J5_Hellbender
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Posted (edited)
2 minutes ago, J5_Hellbender said:

 

You're flying the Halberstadt, apparently. Move your head to the side and you'll see them move. It's a slightly different engine block compared to the Albatros and Pfalz.

 

 

 

It's overcompression on the Mercedes D.IIIa, and it's only present on the Halberstadt CL.II 200hp, as the other planes don't have it (yet).

 

Technically speaking it's pre-ignition/detonation, a.k.a. "knock". The fuel/air mixture is overly compressed at lower altitudes meaning that it often spontaneously ignites due to engine heat and burns up unequally rather than at (or slightly before) TDC, when the piston reaches the spark plugs. This can damage the cylinders over time. In other words: don't use fuel throttle at low altitude.


The ticking occurs in the D7F too. Thanks for the info, I did assume it was a bad thing but glad to have it confirmed. :) It happens without using the altitude throttle. Using a bit of AT stops it sometimes, which I figured was due to enrichening the mixture slightly.

Edited by J3Hetzer

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26 minutes ago, J3Hetzer said:

I might be tripping here but I swear the valve-springs and rockers used to move on the German engines (where they can be seen). Now they're static. Was it a RoF thing or are my marbles rolling?

Talking of engines, what's the ticking noise when the throttle's too far forward at lower alts?

If you're in VR, they don't move. 

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Just now, 71st_AH_Barnacles said:

If you're in VR, they don't move. 


Ah! Thank you. :)

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3 minutes ago, 71st_AH_Barnacles said:

If you're in VR, they don't move. 

 

Seriously? Why is that?

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1 hour ago, 71st_AH_Barnacles said:

To prevent ASW artifacts.


Thank you, I’ve just read up on it and I had no idea this existed. I guess you can add it to the list of reasons I’m holding off on VR for now.

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Posted (edited)
32 minutes ago, J5_Hellbender said:


Thank you, I’ve just read up on it and I had no idea this existed. I guess you can add it to the list of reasons I’m holding off on VR for now.

Yep VR is cool but there are still limitations and compromises.

Edited by 71st_AH_Barnacles
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On 10/6/2019 at 5:14 PM, 71st_AH_Barnacles said:

If you're in VR, they don't move. 

You can see them move in VR, but only after first shutting down the engine, then only for a very short moment just before the engine comes to a stop.

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22 hours ago, J5_Hellbender said:


Thank you, I’ve just read up on it and I had no idea this existed. I guess you can add it to the list of reasons I’m holding off on VR for now.

 

Oooooohh, don’t do that Bender! VR was made for WW1 flying! Bought a Rift S this summer and have not reverted back to monitor/TrackIR once!

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Posted (edited)
On 10/6/2019 at 10:12 AM, J5_Hellbender said:

 

Technically speaking it's pre-ignition, a.k.a. "knock". The fuel/air mixture is overly compressed at lower altitudes meaning that it often spontaneously combusts due to engine heat and burns up unequally rather than at (or slightly before) TDC, when the piston reaches the spark plugs. This can damage the cylinders over time. In other words: don't use full throttle at low altitude.

That's how it worked historically, in Cl.II we have you can go full throttle at sea level and keep climbing until stops knocking somewhere between 1200 and 1500 m, no damage to engine. Not sure if the engine is running at higher power (it shouldn't be due to pre-ignition?) but the RPM are higher...

Edited by J2_Trupobaw
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In fact they move very very very slowly. 

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