Hi all,

As winter rolls around some of us were discussing the modified procedures for flying in the cold at our flight school. There was one thing I couldn't help but remember during my early training days last winter. And I'm still not sure what it was. Maybe someone could clarify.

I was doing the walk around and noticed this green-blue-ish, styrofoam like substance about the size of my fist had completely covered the fuel vent underneath the wing on a 172. It was very cold outside (-15-25C) and the plane had been refuelled within the hour. I want to say that it was some fuel vapour freezing onto the cold metal, but I'm not sure why it would be solid foam?

Or maybe this is just some weird phenomena. Although I seem to recall it happening a few times last winter. The only reason I ask is because a blocked fuel vent could cause fuel travel issues to the engine if severe enough.

Any chance you took a picture? 100ll freezes at a maximum t° of -58°C.

Somebody at your FTU goes around putting a fist-sized lump of floral foam on the fuel vent. Who can say why.

photofly wrote: ↑Mon Nov 30, 2020 7:51 am Somebody at your FTU goes around putting a fist-sized lump of floral foam on the fuel vent. Who can say why.

It's a vent. Those have to be closed when it's cold outside to keep the plane warm. Duuuhh.

I tape off my pitot tube to make sure my ASI doesn't freeze. Works really wel!

digits_ wrote: ↑Mon Nov 30, 2020 8:06 am

I tape off my pitot tube to make sure my ASI doesn't freeze. Works really wel!

Isn't that what the Pitot heat is for?

photofly wrote: ↑Mon Nov 30, 2020 8:17 am

digits_ wrote: ↑Mon Nov 30, 2020 8:06 am

I tape off my pitot tube to make sure my ASI doesn't freeze. Works really wel!

Isn't that what the Pitot heat is for?

No, that drains battery power, so using the pitot heat will reduce the battery life of my ELT. It's a SAFETY thing, so I don't use pitot heat.





In all seriousness though, I wouldn't be surprised if somebody tried to intentionally cover up the vent due to cold weather. Probably a misunderstanding regarding the local cold weather ops.

Perhaps it was a home-made Pitot tube cover misapplied?
Perhaps PilotY mistook the Pitot head for the fuel vent? :-O

Hahaha, yall are funny. I will defend myself and say I know the difference between the fuel vent and the pitot tube. XD. To be more specific. This foam would collapse in my hands, and would more or less break at the lightest touch, before dissolving into the ground. When I told my instructor about it the first time, they didn't care. "As long as the vent was clear were going flying".

PilotY wrote: ↑Tue Feb 23, 2021 4:39 pm Hahaha, yall are funny. I will defend myself and say I know the difference between the fuel vent and the pitot tube. XD. To be more specific. This foam would collapse in my hands, and would more or less break at the lightest touch, before dissolving into the ground. When I told my instructor about it the first time, they didn't care. "As long as the vent was clear were going flying".

I've had leaky wing sump drains on several Cessnas and it will create a blue kool-aid snow cone at the drain in cold temperatures with adequate moisture. Probably the same thing.

BeaverDreamer wrote: ↑Tue Feb 23, 2021 5:04 pm

PilotY wrote: ↑Tue Feb 23, 2021 4:39 pm Hahaha, yall are funny. I will defend myself and say I know the difference between the fuel vent and the pitot tube. XD. To be more specific. This foam would collapse in my hands, and would more or less break at the lightest touch, before dissolving into the ground. When I told my instructor about it the first time, they didn't care. "As long as the vent was clear were going flying".

I've had leaky wing sump drains on several Cessnas and it will create a blue kool-aid snow cone at the drain in cold temperatures with adequate moisture. Probably the same thing.

Ah! That sounds reasonable. I'll be sure to check for that if I ever see this weird thing happen again. Thank you!