G1000 - EGT markings - Stupid question

[VetRepp]

Stupid question but ...

I have an Ovation 2 - IO550G,

What does the white box on the EGT between 1400 -1450  represent? It isn't in the Manual and Garmin didn't know at the last AOPA mtg, so I guess it's a Mooney IO550G specific marking?

See attached thumbnail

 

Thanks Roger

[ArtVandelay]

I would assume that's the normal operating temperature range,

Like the red bar is dangerously high range

[Joe Zuffoletto]

Good question. The G1000 in my Acclaim has the same white box in the same location, but my EGT's run much higher than that. Also, mine doesn't have the red bar on top. I checked my G1000 manual... it shows the white bar and the red bar for the M20TN but doesn't explain what they are.

 

Not a dumb question at all!

 

 

[Danb]

Joe and Roger, I went through all my manuals and also and have no answer as well the pix Joe depicted is the same as in the manual shows the M, TN and R models...

[Marauder]

Could it be a minimum range that they want you to target?

[Txbyker]

I have that too.  Does this box not match the summary engine info on the map page for EGT?  That box should represent the summary EGT readout on the map page for the exhaust collector probe on one side where 3 of the exhaust merge.  There are various threads about the EGT on the summary page being around 100 degrees hotter than the individual EGTs on the engine page.  I was taught that the white box on the map page EGT represents the proper EGT for climb and descent above 3000 feet. Below 3000 it should probably be full rich according to my transition instructor.  Optimally around 1375 climb and descent which actually puts you a bit under the white box.

 

Russ

[Robert C.]

Based on my reading of the AFM for the O2/O3 I surmise it is the target range for mixture during takeoff and climb:

 

TAKEOFF (NORMAL)

Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FULL THROTTLE (2500 RPM)

Mixture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Check and set at top of the white BAR on EGT

Annunciator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHECK

Engine Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHECK for proper indications

Lift Off/Climb Speed . . . . . . . . . . . . . . . . . . . . . As specified in SECTION V (Takeoff Distance)

Landing Gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . RETRACT IN CLIMB after clearing obstacles

Wing Flaps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UP

 

CLIMB (CRUISE)

Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2500 RPM

Manifold Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Inches

Mixture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FULL RICH or white BAR on EGT

Rudder Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AS DESIRED

Airspeed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 KIAS

 

 

Robert

[carusoam]

Sounds like...

That would be the digital representation of the blue box of previous analog gauges on the O...

It combines a range of ROP EGT settings that change during climb phase.

The range (spread) is about 200dF, below 100dF ROP (photo indicates spread is 250dF)

Check your POH for the full description.

Best regards,

-a-

A review of Robert's post above, may be the only reference. It is a small detail, but may be covered in climb procedures as well as instruments.....

[FoxMike]

It looks to me like the white bar is a reference point for best power during takeoff and perhaps high power climb.  In high DA takeoff you need to lean before takeoff to get best power and and shortest takeoff run.  I am guessing it would be easier to reference that bar rather than watching the each EGT bar without a reference.  The red bar is probably giving a reference for max temp to prevent detonation or exhaust cracking for NA airplanes.  For the turbo models the redline also indicates a temp limit for the turbine blades.  

[carusoam]

There should be a reference to the source of the EGT as well. It will indicate that the TC is placed on one side of the engine after the three into one collector..?

-a-

[M20S Driver]

FoxMike:

My flight instructor at Premier Aircraft covered the topic and his comments were in agreement with yours.  He also suggested to use 2400 RPM and lower manifold pressure to stay in the white (or blue) region in cruise climb if possible.

Masoud

[carusoam]

Essentially what we (this community) call the target EGT method of leaning for T/O or climb...?

The O POH documents it, but in a slightly imperfect way...

Best regards,

-a-