Jump to content

Dip Sticks


DC10FE
 Share

Recommended Posts

I got this question from a friend of mine @ Lynden. I haven't been on a Herc since 12/95 so I'm stumped. Any help?

Don R.

"A student asked me how to adjust the dip stick readings for the different fuels. JP-4, JP-5, JET-A, JET-A-1 and so on. Any ideas? Is there a chart? Which fuel is the dip stick calibrated to?"

Link to comment
Share on other sites

A density of 6.7 lbs/gal was to determine the calibration of the 394607-15 dip stick; therefore, the accuracy of the dip stick is affected by the actual density of the fuel and is not to be used to determine the accuracy of the indicator. The airplane must be level when using the dip stick.

I would assume since most of the jet fuels are kerosene based, that they would be close to each other.

I think the normal height loss in approximately 2" per thousand pounds of fuel. I also don't think you use the stick as a fuel measurement tool either. But then again, I don't fly them.

Edited by tinyclark
Link to comment
Share on other sites

JP-4 and Jet B are wide cut gasoline not kerosine based. IIRC JP-4 weighs 6.7lbs/gallon and JP-5/8 weighs 6.9lbs/gallon. The USAF dip sticks are calibrated for JP-4.

If RZ jumps in he will know.

I trusted the dip stick more than the digital gauges when we first got them. The digital gauges settled down after a while or maybe we just got used to them.

Link to comment
Share on other sites

If you flew with an inop fuel gauge you had to dip the tank and verify fuel quantity. There were times when the dip stick was missing, so you just took the broom handle and dipped the tank and then the opposite tank to see how close they were on the handle. Assuming that there was no tilt to the bird. I think 2% was max tilt. Wasn't JP-4 6.4 lbs/gal? JP-5 at 6.9 sounds right.

Link to comment
Share on other sites

If you flew with an inop fuel gauge you had to dip the tank and verify fuel quantity. There were times when the dip stick was missing, so you just took the broom handle and dipped the tank and then the opposite tank to see how close they were on the handle. Assuming that there was no tilt to the bird. I think 2% was max tilt. Wasn't JP-4 6.4 lbs/gal? JP-5 at 6.9 sounds right.

Your right 6.4 and 6.9 If I remember jp8 is same weight as jp5.

Jp4 being wide cut gasoline, Jp5 and jp8 Diesel base

RZ

Link to comment
Share on other sites

Thanks for the replies, guys.

Anyone remember the technical term for the dip stick? I can recall back when I was going through FTD as a A/3C at Langley, the instructor called it a maple gauge. Odd, I can remember garbage like that, but I'll be damned if I can remember what I had for dinner last night!

Don R.

Link to comment
Share on other sites

A few recollections about the Dipstick. It was built for JP-4 and no foam in the tanks. I never heard of a different calibration so I don't think any different dipsticks were ever created. Essentially anyone using JP-4 without foam in their tanks can rely on the actual numbers on the stick the rest of us (OK not me anymore) have to rely on 1. the level on the stick (which is why any long pole will do - but I prefer one I can knife a line/notch if the sun is in a bad position) and 2. the tilt of the aircraft. I used to have an ADI chart which showed the amount to increase or decrease your estimate on based on how much the aircraft was leaning and which tank you were dipping. I got it while I was with Southern Air but if remember correctly it was copied not produced by Southern. It would take a few hours of digging (and at least a six-pack) but if someone is desperate for it and no one else has a copy I could be persuaded to sacrifice for the team and try to find it

Edited by Jake
incomplete information
Link to comment
Share on other sites

Actually, we FEs have to dip the tanks if one of the gauges is broken. I don't even use the scales on the stick. The chiefs have to max the mains before we fly to stay in primary fuel management, so you dip the one with the good gauge, walk over to the symetrical and dip it. If the wet spot matches, you're good. And actually, if the tanks are maxed, when you open the top of wing cap it's pretty obvious.

As far as the markings, I've always been told that the markings are just for JP-4. Like I wrote above, I never use them though.

Mark

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...