767: Do not use WXR during refueling

[Evan]

Found this in a B767 manual. Just curious, why is this hazardous?

[MCM]

It is in pretty much every flight manual, and stems from the day of the VERY high power weather radars. I'm not sure I'd want a high powered beam being around my fuel vapours.

These were the sort that would fry an egg from a hundred paces

[Evan]

It is in pretty much every flight manual, and stems from the day of the VERY high power weather radars. I'm not sure I'd want a high powered beam being around my fuel vapours.

These were the sort that would fry an egg from a hundred paces

They were powerful enough to ignite fuel vapors? What hazard did they pose to ground support personnel? Is WXR restricted when they are present? How do they pose a threat to refueling operations when they are pointed forward and away from the a/c?

[Geebee]

Maybe because fuel vapors eventually might get into it's path. It's forward looking but has quite a wide-angle, doesn't it?

[P3_Super_Bee]

They were powerful enough to ignite fuel vapors?

Some still are. (not to many CWX with that power, if any) But to error on the side of safety, the rules haven't laxed.

Some aircraft types, have different RADAR from one plane to another.. Usually when safety guidelines are written they are written for the stupid... Meaning one rule applies to all. That way one don't have to figure out which aircraft, which RADAR, and what standoffs are needed. Take P-3's, they have 3 different types RADARs used. One, the CWX needs only a 25 foot stand-off, from the nose. One needs, a 75 foot standoff around the whole aircraft(there is an Aft RADAR), One needs a 200 foot standoff from the nose. So our rules state a 200 foot standoff that circles the aircraft. All RADAR are covered with one rule. Didn't matter if CWX was only RADAR being fired, still have to havea 200 foot circle around aircraft standoff.

What hazard did they pose to ground support personnel?

No kids, or girls only. I say this, take a look at me... or any Pilot or Flight Engineer on P-3's. Any of us that flew on the plane in the flight station for more than a year or so, very few of us have boys. The majority have girls, and we're talking about a 95% majority here. It's not proven or anything but, its the only common between all of us, and it's kind of the joke around the P-3 world. "If you want boys, better have 'em before you hit the year mark in the squadron. LOL"

Is WXR restricted when they are present?

Yes. All RADARs have a standoff while RADAR is in operation on the ground.

How do they pose a threat to refueling operations when they are pointed forward and away from the a/c?

Winds could blow fumes forward, and some RADAR can have up to a 270 degree sweep, don't just point forward.

Or... Not sure you would see to much on airliners, maybe at remote airports without airbridges, but take P-3's we sometimes fuel with the truck at the nose of the aircraft with the fuel hose running under the wing to the refuel port. This does two things for us. 1. Easy evac route for truck if something goes wrong(IE fire) and two the APU exhaust is not blowing on the truck if parked behind the wing. Though we have done that for like 40+ years without problem, and most Navy bases P-3's(Manuals state this is the preferred method) still get fueled this way. The winney ass Jarheads fuel from the front, and did have same type issue from an Air Farce jackass with same concern. He also didn't want to fuel from the front under APU power because the APU exhaust would have been right next to the truck. (APU exhaust on a P-3 is on the starboard side of the forward fuselage bout wing level just aft of the flight station. The flight engineer actually sits on top of the APU). But the Air Farce are wacked when it comes to refueling to begin with...

HF Radio transmition is also not permitted during fueling.