Engine Time vs. Airframe Time

[John]

Please help me understand how the Engine Hours can be so much less than the Airframe hours.  I've had my 2016 - P2008-Turbo for only a couple of months.  I started noticing the discrepancy between Engine hours and Airframe hours.  For example, over the past several weeks I've flown about 10 times.  Over the course of those flights the G3X tells me that I've added 9.3 Engine hours and 14.7 Airframe hours. 
I probably sat in the aircraft with just auxiliary power (to study the avionics) for maybe three hours.  I didn't, however, notice that the Airframe hours were changing during that time.  I could be wrong about that though.  But I notice that on each flight the Engine hours are less than the Airframe hours.
I suspect that the settings in the G3X are dictated by Rotax and that Engine hours are accumulated on a variable basis.  Sort of like, the harder it works, the more time it shows.  Kinda like Indiana Jones saying when asked about his age, "It's not the years, it's the mileage."
Your thoughts Tecnam guys? 

[Glenn]

John,

A detailed explanation can be found in the G3X installation manual pages 32-150 and 32-151 (revision AA).  


Glenn

     

[John]

Thanks Glenn,

I'm told that Engine Time Configuration values for the Rotax 914-Turbo engine should be:
Record Mode = "Enabled"
Minimum Recording RPM = 300
Standard Recording RPM = 5500
Maximum Recording RPM = 8000

That sound about right?
The engine hours vs airframe hours in my example seem reasonable?
The discrepancy got my attention when looking forward to my 100 hour (Engine Time) inspection.

Thanks again,
John

[Glenn]

John,

Every G3X I've seen (in the U.S.) was set up so that recorded engine time was less than airframe time.  They may choose different settings in Europe but what you've got is pretty standard here.  "Standard Recording RPM = 5500" means that an hour running the engine at 5500 RPM will record one hour on the engine time.  Engine time would be recorded as less than one hour if you cruised for an hour at less than 5500 RPM.  

Hope that makes sense.

Glenn

[Cluemeister]

So do you put in Total Time or Engine time in your logbook after a flight?

[Glenn]

Mar 15, 2017 23:51:01 GMT Cluemeister said:

So do you put in Total Time or Engine time in your logbook after a flight?

The Pilot's Log Book entry would be total time (taxi time plus flight time = total flight time).

FAR Definitions 1.1
Flight time means:
 (1) Pilot time that commences when an aircraft moves under its own power
for the purpose of flight and ends when the aircraft comes to rest after landing


Glenn

[John]

Thanks again Glenn. I'll pay no attention to total time when it comes to 100 hour engine inspections and oil change intervals.

[Ed Midgley]

I went into the sub menu and shut off the engine time. My plane was set up wrong and it was adding engine time at twice the airframe time. I use airframe time for both now. 
Ed

[jetcat3]

Hey y'all,

Any idea why our P2008 lists engine time only? Thanks.

[Cluemeister]

Mine shows both Engine Time and Total Time.

[MarkGregor]

Drew,


When some of the planes were delivered from the factory (including yours) the engine was set to 2700 as full RPM in the G3x. This is the correct for a Lycoming or Continental. The Rotax should be set to 5500 RPM. When set this way engine hours will add up aprrox twice as fast as they should. The factory suggested to turning the engine hours off and only use the airframe hours.


Mark

[jetcat3]

Mark,

Sounds good. Any idea how to turn off the engine time hours and just record airframe time? Thanks.


Drew

[Glenn]

Drew,


1. Enter configuration mode: Push and hold the menu key while powering on the GDU 45/46.

2. Select Engine and Airframe

3. scroll through and select from the choices to change recording (detailed explanations are in the install manual)

4. Be sure to select SAVE before exiting



The Installation Manual is a great reference.
Current revision is AB.
Download at: support.garmin.com/support/manuals/manuals.htm?partNo=010-00G3X-00&language=en&country=US

Glenn

[jetcat3]

Glenn,

Thank you so much! Appreciate all of that information.

Ed,

Did your P2008 have Airframe time listed in addition to engine time?

Drew