Gas cap engraving

[cdeerinck]

Is their any logic to some of the things that people engrave on their gas caps?

I understand putting "100LL Only", or "AVGAS". The reasoning is so the wrong stuff won't be accidentally put in.

I understand putting your N number on, in case a Cap gets "lost".

I understand open/close positions and/or directions, for people who don't know how to use the cap. I would question why they are filling my airplane then, so I don't agree with that logic, but I can understand it.

Things I don't understand the reasoning behind at all, are:
- Capacity (e.g. "21 US Gallons")
- Aircraft type (e.g. "RV-8")

Can anyone help me understand why? Have any of you seen other things there, and thought "That's a good idea!" ?

[Mike S]

Up North Aviation is who you want to talk to. http://www.upnorthaviation.com/fuel-cap-engraving.html

Lots of great reviews in the "Reviews" section. http://www.vansairforce.com/communit...c&daysprune=-1

Example of his offerings;

[rightrudder]

I went with:

100LL only
17.7 gal. usable

Short & sweet.

[Mike S]

Originally Posted by cdeerinck

Is their any logic to some of the things that people engrave on their gas caps?

I understand putting "100LL Only", or "AVGAS". The reasoning is so the wrong stuff won't be accidentally put in.


Things I don't understand the reasoning behind at all, are:
- Capacity (e.g. "21 US Gallons")

Pretty sure you will find that fuel type and quantity are required by FAA regs.

[cdeerinck]

Pretty sure you will find that fuel type and quantity are required by FAA regs.

Mike S -- Not disagreeing at all, as this might be the most important reply of all. Can you point me to the Reg?

[az_gila]

Originally Posted by Mike S

Pretty sure you will find that fuel type and quantity are required by FAA regs.

Just looked it up...

Apparently QTY is not directly in the Part 23 requirements, but it says other markings may be required by a certified aircraft AFM. Fuel type is a required marking

I think the aircraft manuals might specify it to help with W&B calculations.

PS above is for certified aircraft.

[cdeerinck]

If it is FAR 23.1557, it only need say AVGAS 100LL, not capacity.

[Mike S]

Originally Posted by cdeerinck

Mike S -- Not disagreeing at all, as this might be the most important reply of all. Can you point me to the Reg?

No idea about reg number, but I recall having to label the tanks for my airworthiness inspection.

[az_gila]

Originally Posted by cdeerinck

If it is FAR 23.1557, it only need say AVGAS 100LL, not capacity.

Correct, but the Type Certificate details are added regulatory requirements for certified aircraft and they do all seem to add fuel qty. as a required placard.

Even the lowly C-150... page 18 -

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/14b9f17e0cdcc2ae862578bf004875be/$FILE/3A19%20Rev%2048.pdf


My Tiger TCDS does the same, but that has the added feature of a tab to label. The C-150 is a simple tank.

[cdeerinck]

Gil - Thanks for that. I will add the capacity, because "why not?". If there is a reason for certified planes to have it, it probably has some value (don't flame me for that comment).

I did notice that 23.1557 also says that the fuel selector is supposed to indicate capacity for each separate source, but I have never seen that on any RV that I looked at. So it would need to say 21 US Gallons on both the right and left side of the fuel selector. That I will not do, unless told that it is mandatory during my inspection.

Good info guys, thank you very much!