Exporting ROTAX 912 files to SavvyAnalysis

[ssbn608]

I now fly a Pipistrel Sinus motorglider with a carbureted 80 HP Rotax 912UL2 engine (I got rid of the aircraft I have posted inquiries about a few years ago, with a 912iS engine, by crashing and totalling it in a wind shear incident.; I say this so no one is confused about what engine I'm talking about...) After a flight, I download files from my SkyView Classic, and upload the User_Log_Data file to the SavvyAviation website for analysis. When I look at the list of flights in my aircraft, every line has an alert for "HI CHT". When I look at the logs, I see traces for CHT's 1, 2, 3, 4, CHTL, and CHTR. The alarms seem to be occurring because of the readings on CHT1. But in point of fact, there are NO SENSORS for CHT 1, 2, 3, and 4 on my aircraft's Rotax 912 engine; CHTL is a sensor mounted on the #2 cylinder head, CHTR is mounted on the #3 cylinder head. There are NO OTHER CHT temperature sensors embedded in the cylinder heads. CHTL, CHTR, and Coolant temperature track as engine load is changed (though Coolant temperature deviates from CHTL & R temperatures as airspeed changes... which makes sense, since cooling in the radiator is a factor). CHTL, CHTR, and Coolant temperature start ( (for a cold start) from temperatures reflecting actual Outside Air Temperature, however CHT 1, 2,3, 4 start at 4 very different temperatures from each other, do NOT reflect actual outside air temperature at start, and do not track along with CHTL, CHTR, or coolant temperature, thought they do change a few degrees during aircraft operation... though without much regard to what the aircraft is doing (climbing, descending cruising, taxiing).

For example, on my most recent fight.

at system startup, before engine was started (after the aircraft had been sitting for days);

CHT1 114
CHT2 14 (yes, 100 degrees lower thatn CHT1...)
CHT3 57
CHT487
CHTR (#2) 25
CHTL (#3) 25
Coolant 28.2


13 1/2 minutes later, after a mile of taxiing, and runup,, prior to takeoff

CHT1 127
CHT2 26
CHT3 66
CHT4 107
CHTR (#2) 93
CHTL (#3) 95
Coolant 84.4

34 minutes after startup, after doing a touch and go,followed by a climb to 8000' AGL,


CHT1 145
CHT2 46
CHT3 84
CHT4 127
CHTR (#2) 94
CHTL (#3) 94
Coolant 78.7



The traces of CHT 1, 2, 3, and 4 describe 4 parallel arcs , with occasional small spikes - at exactly the same moment on all four channels, spikes not reflected on the other traces on the Savvy Analysis graphs.


I think it's pretty clear that the values for CHT 1, 2, 3, & 4 are bogus values resulting from, perhaps, wiring in the Dynon SkyView system that are NOT connected to any sensors.

I know I can go into the graphs, and individually hide traces for CHT 1, 2, 3, & 4. Is there any way to set a universal default saying disregard CHT 1, 2, 3, & 4, and to not issue flight alerts for them? Or tell SkyView not to report these values at all?

How can I check that flight alerts will be set for high values of CHTL and CHTR?

 

[Raymo]

The HI CHT warning may be related to your aircraft profile "CHT Warning Temperature" setting. The incorrect temps are very likely due to the Savvy parser, which expects certain things from the Dynon CSV file. I suggest emailing them with your issue to see if they can add support for your setup to properly parse the files.

 

[ssbn608]

Thanks. Will be discussing it with them too. But just wondered if this was an issue any of the MANY people flying 912's have already experienced and dealt with.

 

[Raymo]

I sent an email to Savvy on your behalf. Will reply when I hear back from Joe.