Extended exhaust?

[ChrisRikli]

I saw a C172 on the tarmac the other day that had this really extended exhaust pipe that terminated behind the landing gear, about underneath the baggage compartment. What would the purpose of this have been?

I have included a professionally rendered artists conception to help you visualize this:

 

[dmccormack]

Mapping and other low-level imagery singles have this mod.

I asked a mapping pilot about this and he said it helps divert the exhaust so the images aren't distorted.

Everskyward did mapping, I think? She may provide more details.

 

[TMetzinger]

Three possibilities:

The airplane could have come from europe, where noise standards are stricter and a real muffler is required (less likely).
The airplane has a tuned exhaust like a PowerFlo system, which has longer pipes from the cylinders and an overall longer length to give it more efficiency and power. (This is the likely answer).
The airplane has the exhaust extended so it will bypass a belly-mounted sensor (camera, IR, other) and not interfere.

 

[ChrisRikli]

Mapping and other low-level imagery singles have this mod.

I asked a mapping pilot about this and he said it helps divert the exhaust so the images aren't distorted.

Everskyward did mapping, I think? She may provide more details.

That would be it; these guys were working for LandCare taking shots for Bing.

I wonder if it reduces cabin noise?

 

[Let'sgoflying!]

Comme Ça ???

oh wait you said behind the gear, stby 1...

couldnt find one but sounds like an aerial survey a/c

 

[KSCessnaDriver]

You mean an exhaust like in the picture I linked here? http://www.airliners.net/photo/Cessna-172M-Skyhawk/1083879/L/

 

[Everskyward]

Mapping and other low-level imagery singles have this mod.

I asked a mapping pilot about this and he said it helps divert the exhaust so the images aren't distorted.

Everskyward did mapping, I think? She may provide more details.

All of the single-engine mapping airplanes I flew had a modified stack in order to keep the exhaust from distorting the images. Most of them just had a 90 degree bend in them but I can imagine other more fancy setups like some of the ones pictured.

 

[weilke]

I saw a C172 on the tarmac the other day that had this really extended exhaust pipe that terminated behind the landing gear, about underneath the baggage compartment. What would the purpose of this have been?

I have included a professionally rendered artists conception to help you visualize this:

Kind of like this ?

That is how a Gomolzig muffler system looks like. Combined with a 3 or 4-blade prop it can reduce external noise considerably.

 

[ChrisRikli]

You mean an exhaust like in the picture I linked here? http://www.airliners.net/photo/Cessna-172M-Skyhawk/1083879/L/

This, exactly.

 

[Ken Ibold]

This, exactly.

Ah, a relief tube for someone with a very large bladder.

 

[VTC_WS6]

Comme Ça ???

oh wait you said behind the gear, stby 1...

couldnt find one but sounds like an aerial survey a/c

Just saw that exact setup on what looked like an old Cardinal at PGD this past Saturday.

 

[timrj]

Three possibilities:
...
The airplane has a tuned exhaust like a PowerFlo system, which has longer pipes from the cylinders and an overall longer length to give it more efficiency and power. (This is the likely answer).
...

Definitely NOT a powerflow.

 

[Capt. Geoffrey Thorpe]

I saw a C172 on the tarmac the other day that had this really extended exhaust pipe that terminated behind the landing gear, about underneath the baggage compartment. What would the purpose of this have been?

I have included a professionally rendered artists conception to help you visualize this:

Looks more like a 182 than a 172 to me.

 

[Pilawt]

I parked next to one of those at Provo UT a couple of years ago ...

 

[TMetzinger]

I parked next to one of those at Provo UT a couple of years ago ...

That's a sensor rig - you can see the sensor in the baggage door.

 

[Pilawt]

That's a sensor rig - you can see the sensor in the baggage door.

The one in the airliners.net photo linked in Joel's post has a similar hole in the bag door -- but patched over.

 

[Curious Bloke]

Hi I actually need one of those to circumvent the camera installed beneath. Do you know any company who can produce that type of extension for me? Thanks

 

[Rgbeard]

First post - resurrecting a nearly 13-year-old thread. That's not a record, but close.

But I get why.

 

[Skyrys62]

And funny (cool) that some of the original folks are still online at this moment..

 

[FCAJR8630]

Hey - at least he used the search function to find something relevant!