[mcems]

I have 13 hours of flight now on 124BJ. Just s few notes on a couple items.

1. after the maiden flight I took the cowling off to look things over . All looked good. Then a few more hours and pulled the cowling off agian top and bottom. Sure glad I did. I found the oil line that runs from the pump to the cooler had moved some how and was up against exhaust pipe . I was just sure when I put the lower cowling on and attached the oil cooler it was good. Well it wasnt and it was my fault . I had misrouted that line. After looking closer at the drawings I could see my mistake. The line looked like it really got hot . It had melted into the the outside sleeve. I took no changes and ordered a new one from Vans . I replaced it and made sure of my routing and clearances on all the lines one more time.

IT pays to check and double check in the testing phase.

2. On 2 occasions when I would startup and taxi out I would get low fuel pressure reading and warning . It would only last for a short time then return to normal. At full static run up it would hold in the normal ranges . I could not make it drop agian. Also it never dropped in flight. Well on my last fly I taxied out and low fuel came on again. This time it dropped to 1.2 PSI . When I did the static run up it would drop .When I would idle back down it would come up agian but still not in the normanl range. SO OK thats tells me we have a problem. As the engine reguire more fuel the pressure dropped. Restricted flow some place. My first thought was what if the vent was plugged. I shut it down on my runway and took the fuel cap off . Then restarted and the problem was gone. I stayed on the ground and did several long run ups the pressure stayed steady in the normal range. OK I took the cap back to my hangar and drilled 2 additonal holes for venting. I have not had any problems since and have flown 3 hours since adding the vent holes. I am not sure what I fixed because I looked close to see if the vent hole was plugged It did not appear to be and I could get air to pass thru the hole. May be a bug was in there?? At any rate when I added the holes my problem went away. The only other cause I can think of is an intermittent obstuction in the fuel line its self that just happen to free its self when I shut down and pulled the cap off to vent the tank. I might do some more checking on the fuel system. Just something you guys might want to be aware of.




Well now the good news . My wife helped a lot on this project and she was ready for the first ride . Well she got it on Sunday She loved it. Also got my son up for a spin.


Brad Stiefvater
Salem SD

 

[Geico266]

Thanks for posting the info Brad. Since the -12 is a new model it is nice to post such items so we can stay ahead of the curve.

So everyone knows, other RVs fuel tanks have vents that slightly pressurize the tanks as the plane flies. The RV-12 fuel tank basically gavity feeds the electric fuel pump with a #40 vent hole drilled in the standard RV fuel cap and fuel cap back plate. If it gets plugged we become a glider. Maybe a good time to look at this potential "Achilles' heal" of the -12 fuel system.

Maybe I need to carry an ice pick in the plane just in case?

 

[Platyius]

How much clearence

Brad, how much clearence do you have now, mine is very close and I wonder if it is too close. Also the other exhaust pipe is close to the fiberglass, any problem there.

Tony

 

[Jim P]

Phase 1?

Just curious since I don't know much about the ops limits for the -12, but what's the general Phase 1 (if there such as thing) for a -12.

 

[Geico266]

Just curious since I don't know much about the ops limits for the -12, but what's the general Phase 1 (if there such as thing) for a -12.

If you are asking about hours in Phase 1 it is 5-10 hours for the RV-12 depending on the DAR. There seems to have been some confusion early on, but the consensus seems to be 5 hours now.

 

[N162RV]

Be sure to check all electrical connections as well... Erratic readings are often due to poor electrical connection... especially grounds....

 

[mcems]

Brad, how much clearence do you have now, mine is very close and I wonder if it is too close. Also the other exhaust pipe is close to the fiberglass, any problem there.

Tony

I have about 1 inch clearance now on all the oil lines. Darrel At Vans said they like to see a least an inch. . I have only 1/4 inch between the 90 degree fitting that comes out of the bottom of the engine and the muffler. I have asked a few other and they have the same. I think its about all you can get when positioning the muffler. I have seen no evidence of it touching or rubbing. Yes the fiberglass is close but have had no issue there.

Brad

 

[mcems]

Just curious since I don't know much about the ops limits for the -12, but what's the general Phase 1 (if there such as thing) for a -12.

I was issued 10 hours and 50 nautical miles. I think 10 hours is fine. It would be difficult to get everything checked out good in 5 hours. For me the first 5 hours I was very busy just getting the feel of the plane. I have been flying a high wing pusher (Challenger 2) so it took me a while. I guess it would be different for those who have been flying something closer to the 12.


Brad Stiefvater
Salem SD

 

[scsmith]

extra vent hole non-conforming?

A minor nit perhaps...but is it actually OK for the builder to drill the extra vent hole in the fuel cap? Doesn't the airplane need to conform 'exactly' to the plans?

 

[rvbuilder2002]

A minor nit perhaps...but is it actually OK for the builder to drill the extra vent hole in the fuel cap? Doesn't the airplane need to conform 'exactly' to the plans?

As long as a modification is done after initial certification (which includes the flying done in phase 1), and is documented in the aircrafts records, it is legal...

Though in my opinion it had absolutely no effect on the the fuel pressure reading.

 

[Mel]

Phase I flight testing for ELSA is....

Just curious since I don't know much about the ops limits for the -12, but what's the general Phase 1 (if there such as thing) for a -12.

5 hours minimum. However, the DAR can add more hrs if he feels that it is necessary. Although I can't think of a good reason on a kit-built ELSA unless the workmanship is poor.