# Why does the B-2 Spirit have a pattern of thin white lines?

Northrop Grumman's B-2 Spirit bomber is mostly black or dark grey, but has a symmetric pattern of distinctive, thin white lines painted on its wings and fuselage. I have not been able to find anything similar on other airplanes, so why does the B-2 have these lines and what is their purpose?

• Comrade's username checks out :) – ymb1 Nov 19 '19 at 10:07

@RAC and @Hobbes are right. I found a high res photo on defense.gov.

The crop below shows WALKWAY and NO STEP instructions indeed. Similar to what you'd find on a jetliner's wing.

It makes me wonder though why the person below did not abide.

• The guy looks like he's wearing special shoes/socks – slebetman Nov 20 '19 at 9:01
• @slebetman I doubt they'll let you clamber over it with your trainers/slippers/stilettos on. – Lightness Races in Orbit Nov 20 '19 at 17:53
• Also grr tucson.com's lazy geoblocking strikes again! Extra amusing that they don't bother to take into account that the phone number will differ for their target audience. All around, very "f%\$! the rest of the world" there. – Lightness Races in Orbit Nov 20 '19 at 17:53
• He's making a shortcut. – stackzebra Nov 20 '19 at 20:52

At a guess, they're 'walk here' lines, to show where you can walk, with the rest of the airframe being 'don't walk'.

• Correct. Like the other decals (serial numbers, Star and bars, panel outlines), they're light gray to reduce visibility at a distance compared to a bright color like white. – Hobbes Nov 19 '19 at 15:20
• they're light gray to reduce visibility at a distance good thing too. We wouldn't want those pesky enemies knowing which parts of our wings are safe to walk on! – dwizum Nov 19 '19 at 19:36
• @dwizum Probably more relevant for the CUT HERE instructions on the cockpit – Bergi Nov 19 '19 at 22:51
• @dwizum: I realize you're joking, but to put things in perspective: back in the '80s (when I was in the Air Force) they were working on improving camo on F/B-111's, but the F-15 pilots were seeing them when they were sure they shouldn't. Eventually, an F-15 pilot admitted that they couldn't see the plane--what they could see was the pilot's shiny white helmet. Shortly after that, new helmets were also flat grey, and they issued camouflage tape to cover existing helmets. – Jerry Coffin Nov 20 '19 at 23:12
• @JerryCoffin that sort of thing is also why some air forces paint "fake" cockpits on the underneath of their aircraft, literally just to confuse an adversary for a split moment (and such moments can make or break you in a dog fight)... – Moo Nov 21 '19 at 0:06

Military aircraft, believe it or not, have relatively thin sheets of aluminum, titanium, composite, or honeycomb panels for much of the airframe. To prevent these more fragile areas from being damaged, the wing is marked with where it is and isn't safe to walk. As for the white footwear, these are typically just the equivalent of the disposable headgear you see doctors wear when they go into surgery on any doctor show on TV. They're to protect the paint, to prevent scuffs, and to prevent damaging any special paint coatings such as radar absorption (stealth).

• It's unclear from the photos – is the wing generally unsafe except for the marked safe areas, or is it the opposite? – user1686 Nov 22 '19 at 10:14