Cambridge 302 question

[[email protected]]

Hello Guys. I am restoring another 1-26 and have a spare older 302 I would like to use. Have any of you used that vario without the external TE probe, setting it to the internal compensation mode? The manual for it does’nt recommend it but I would like to save the bother and drag associated with installing an external probe.

I use a 302 with external TE in my other machine and it works great but have never experimented with the internal compensation setting. Any shared experience comments sure welcomed.

[JS[_5_]]

On Thursday, January 23, 2020 at 3:00:12 AM UTC-8, wrote:
> Hello Guys. I am restoring another 1-26 and have a spare older 302 I would like to use. Have any of you used that vario without the external TE probe, setting it to the internal compensation mode? The manual for it does’nt recommend it but I would like to save the bother and drag associated with installing an external probe.
>
> I use a 302 with external TE in my other machine and it works great but have never experimented with the internal compensation setting. Any shared experience comments sure welcomed.

I remember it working fine on electronic TE.
Refer to the manual for pneumatic connections and TE compensation setup.
Jim

[Tango Eight]

Works fine if you have high quality, unshared, co located pitot and static (e.g. triple probe) sources. With typical 1-26 sources, not so much.

I suggest using TE probe.

T8

[[email protected]]

I have a 302 in my Libelle that is set at 100% electronic compensation. Right beside it I have a Borgelt B40 that is connected to my TE probe. There is little if any difference between the two. I absolutely believe you'll be happy with the 302 and pure electronic compensation.

Robert

On Thursday, January 23, 2020 at 5:00:12 AM UTC-6, wrote:
> Hello Guys. I am restoring another 1-26 and have a spare older 302 I would like to use. Have any of you used that vario without the external TE probe, setting it to the internal compensation mode? The manual for it does’nt recommend it but I would like to save the bother and drag associated with installing an external probe.
>
> I use a 302 with external TE in my other machine and it works great but have never experimented with the internal compensation setting. Any shared experience comments sure welcomed.

[Dan Daly[_2_]]

On Thursday, January 23, 2020 at 6:00:12 AM UTC-5, wrote:
> Hello Guys. I am restoring another 1-26 and have a spare older 302 I would like to use. Have any of you used that vario without the external TE probe, setting it to the internal compensation mode? The manual for it does’nt recommend it but I would like to save the bother and drag associated with installing an external probe.
>
> I use a 302 with external TE in my other machine and it works great but have never experimented with the internal compensation setting. Any shared experience comments sure welcomed.

There was a Johnson report, "DEVELOPMENT OF A TOTAL ENERGY SYSTEM FOR THE PW-5 SAILPLANE By Richard H. Johnson, Published in Soaring Magazine, April 1998" which describes a simple fuselage-mounted short TE probe that worked well. It includes instructions for building your own probe. It should be in the SOARING archive.

[MNLou]

I use a 302 with electronic compensation as a back up vario and find it works just fine.

This is especially true when I have the sustainer engine running. The engine seems to affect the T/E probe for my other vario and causes it to be a little wild.

Lou

[Eric Greenwell[_4_]]

wrote on 1/23/2020 3:00 AM:
> Hello Guys. I am restoring another 1-26 and have a spare older 302 I would like to use. Have any of you used that vario without the external TE probe, setting it to the internal compensation mode? The manual for it does’nt recommend it but I would like to save the bother and drag associated with installing an external probe.
>
> I use a 302 with external TE in my other machine and it works great but have never experimented with the internal compensation setting. Any shared experience comments sure welcomed.
>
It worked well in my ASH 26 E, which has excellent fuselage pitot/static. I did
not use the tail probe because that is badly affected by the prop wash during the
launch.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[Tim Taylor]

On Thursday, January 23, 2020 at 4:00:12 AM UTC-7, wrote:
> Hello Guys. I am restoring another 1-26 and have a spare older 302 I would like to use. Have any of you used that vario without the external TE probe, setting it to the internal compensation mode? The manual for it does’nt recommend it but I would like to save the bother and drag associated with installing an external probe.
>
> I use a 302 with external TE in my other machine and it works great but have never experimented with the internal compensation setting. Any shared experience comments sure welcomed.


I have used the 302 as my back-up logger and vario on electric compensation only. I run my other vario on TE and see very little difference. If I have a TE failure it is nice to know the 302 will work well.

[[email protected]]

Thanks for all the comments guys, sure appreciate it. Not having to deal with mounting the TE probe for the 302 lightens my load of restoration chores lol.
Dan