B21 Raider

[mowens]

Today will be the public unveiling of the B21 Raider strategic bomber by Northrop Grumman. It is meant to be a replacement for the B1 and B2 bombers. The B52s are immortal. They'll stay in service for the foreseeable future. The air force initially wants 100 but would like to have 200.
Spirit Aerosystems is one of seven publicly acknowledged vendors.

Looks like there will be a youtube live stream in 8 or 9 hours.

[CNCAppsJames]

Those B-52 airframes...  🦾

I'd there are at least a few grandkids of original pilots flying them today. It's certainly not out ofnthe realm of possibility. 

[Matthew Hajicek]

I wonder if it would be worth making a brand new run of B-52's.

[JParis]

I wonder if it would be worth making a brand new run of B-52's.

The last one was delivered in 1962....60 years ago....been updated numerous times.

As well as this baby has served the US, it's likely time to let them go.  As expensive as these newer planes are, I have to imaging the startup costs of that line would be just as massive.

Plus, the mission, the mission parameters and today's modern weaponry have all changed. This requires new equipment.

 

[CNCAppsJames]

.....As expensive as these newer planes are, I have to imaging the startup costs of that line would be just as massive.

Yeah, I concur. Even if we had all the tooling, drawings, suppliers, etc... for it, manufacturing methods and the skills those tradespeople posess today are WAY different. 

Like we can't just make more Rocketdyne F1 rocket motors. It's not even that anything was destroyed, necessarrily it's the machinists notes, welders notes, electricians notes, engineer's notes that never made it back to the manufacturing routing instructions that were in a retired guy's toolbox... that knowledge/experience is gone forever and near impossible to replicate.

It's likely we can replicate anything from the electronic  PLM era on. Prior to that it's more than likely cheaper to start over from scratch. IMHO.

[CNCAppsJames]

Furthermore, theoretically we should be able to take a complex assembly and just make all the parts and it should just go together. Just like the drawing shows. But we know there's this little gremlin hiding in the shadows and his name is Tolerance Stack. He's a real bugger and he's the reason why skilled assemblers are still required even in this era of high precision.

Thinking out loud here... If a Boeing 737 MAX were made and EVERYTHING metal was made at the max length, width, and height, I wonder how much larger the airframe would be? And people would still put that thing together and make it airworthy.  That's skill. 

JM2CFWIW 

 

[JParis]

Yeah that's a huge issue... what is and isn't documented.

I remember modeling an F15 airframe component.... the print tolerances just didn't add up right to create the form as toleranced on the print.

The company I was working a contract through needed to go upstream and they had to go through the chief builders log to find what they needed to do to make things fit...

[mowens]

My dad worked on B52s back in the 60s when they would come back from Vietnam.

[gcode]

And you prolly have 1/2 ton of primer, undercoat, and top coats after a couple of repaints too.

Years ago I read that the weight of a 747 could vary by 40K pounds due to tolerance issues
and that a coat of paint added 15K pounds

[RobertELee]

Years ago I read that the weight of a 747 could vary by 40K pounds due to tolerance issues
and that a coat of paint added 15K pounds

It takes about 120 gallons to paint a 747, a gallon of paint weighs around 12lbs. So more like around 1500lbs.

[gcode]

a gallon of paint weighs around 12lbs. So more like around 1500lbs.

looks like I got a decimal point wrong
I hate it when that happens

[mowens]

Furthermore, theoretically we should be able to take a complex assembly and just make all the parts and it should just go together. Just like the drawing shows. But we know there's this little gremlin hiding in the shadows and his name is Tolerance Stack. He's a real bugger and he's the reason why skilled assemblers are still required even in this era of high precision.

JM2CFWIW

We can get a lot closer to the mark on the first try now since everything is digital. Before, plaster models were built to duplicate critical surfaces. For tooling, fiberglass splashes would be made using the master model, which would transfer relevant data as well as the contour.

[TylerBeer]

Excited to see more photos.

Years ago a B2 flew real low over my parents' place while we were out on the patio, it was one of the coolest things I've ever seen.

[gcode]

One morning in 1977 I was on the rifle range at the Central Training Area on the island of Okinawa Japan just as the sun was coming up. I looked up and saw an SR-71 about 500 feet up lowballing into Kadena Air Force base 30 miles south of me.
I'm guessing it was flying low trying to avoid radar on a return flight from a mission over North Korea, the USSR or China. That was a once in a lifetime sight

[TylerBeer]

One morning in 1977 I was on the rifle range at the Central Training Area on the island of Okinawa Japan just as the sun was coming up. I lo0oked up and saw an SR-71 about 500 feet up lowballing into Kadena Air Force base 30 miles south of me.
I'm guessing it was flying low trying to avoid radar on a return flight from a mission over North Korea, the USSR or China. That was a once in a lifetime sight

with 32 built, I wonder what number it was!


I can do without war, but warplanes will never cease to be fascinating and amazing.  As a kid I was obsessed with the F-14