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XB-1's wings are officially closed out

blog.boomsupersonic.com

11–20 of 180 posts

Re: XB-1's wings are officially closed out

#11
post #3

I keep wondering if planes could benefit from the new materials developed by SpaceX. If they really have a stainless steel that's significantly lighter, it could be a game changer.

You are not going to get SS with the strength/weight of carbon fiber. Just no way. SpaceX is using SS for its favorable thermal properties that CF doesn't have.

Re: XB-1's wings are officially closed out

#12
post #6

i'm in no way qualified to give any praise/criticism, it just caught my attention (from the linked post on their cockpit/fuselage bonding https://blog.boomsupersonic.com/20-hour-bonding-event-speeds... ) "It’s the following morning and bonding appears to be successful, but it’s essential to confirm that the bond lines are shaped correctly or “filleted.” A member of the engineering team, who is certified in the proces…

Yea, not very scientific. Seems like ultrasonic tests would be good here. I think they do something similar to check welds on ships.

Re: XB-1's wings are officially closed out

#14
post #6

i'm in no way qualified to give any praise/criticism, it just caught my attention (from the linked post on their cockpit/fuselage bonding https://blog.boomsupersonic.com/20-hour-bonding-event-speeds... ) "It’s the following morning and bonding appears to be successful, but it’s essential to confirm that the bond lines are shaped correctly or “filleted.” A member of the engineering team, who is certified in the proces…

Reminds me of the Apollo parachute packers, highly manual job with specialized human-only techniques.

Re: XB-1's wings are officially closed out

#15
post #3

I keep wondering if planes could benefit from the new materials developed by SpaceX. If they really have a stainless steel that's significantly lighter, it could be a game changer.

Not in this case. With SpaceX they also need high (de-entry, Mach heating) and low temperature (cryo fuel & oxygen) resistance but in the case of Boom the surface won’t heat enough to need high temp materials. That said, I’m not sure their choice of materials is the good one for a startup.

CF prices have come down rapidly in the past 20 years and it's becoming the standard structural material for original airframes. It's more workable and less exotic than it was before. I think most, if not all, aviation startups are using it, like the Icon A5.

Re: XB-1's wings are officially closed out

#17
This is probably a dumb question, but if the wings are now closed forever, how does one do maintenance or inspection of the mechanical flight control systems composed of cables and pulleys? Is the expectation that the XB-1 is going to be used in flight for far less than the design life of those mechanical systems?

Re: XB-1's wings are officially closed out

#18
post #6

i'm in no way qualified to give any praise/criticism, it just caught my attention (from the linked post on their cockpit/fuselage bonding https://blog.boomsupersonic.com/20-hour-bonding-event-speeds... ) "It’s the following morning and bonding appears to be successful, but it’s essential to confirm that the bond lines are shaped correctly or “filleted.” A member of the engineering team, who is certified in the proces…

Yea, not very scientific. Seems like ultrasonic tests would be good here. I think they do something similar to check welds on ships.

Ultrasound inspection is very common for multi-layer composite construction. There are large machines which transmit the ultrasound through a water jet, for use in mapping the characteristics of curved surfaces. This water jet ultrasound non-destructive testing (NDT) is used in aerospace for carbon laminates.

That said, 'tapping' is an acoustic inspection technique, and can get good results.

I am not sure why they selected the manual option, but they probably have a reason.

Re: XB-1's wings are officially closed out

#19
post #6

i'm in no way qualified to give any praise/criticism, it just caught my attention (from the linked post on their cockpit/fuselage bonding https://blog.boomsupersonic.com/20-hour-bonding-event-speeds... ) "It’s the following morning and bonding appears to be successful, but it’s essential to confirm that the bond lines are shaped correctly or “filleted.” A member of the engineering team, who is certified in the proces…

Yea, not very scientific. Seems like ultrasonic tests would be good here. I think they do something similar to check welds on ships.

yes, ultrasound on ship welds, and if i remember correctly - on some forged and other way fabricated/processed parts too. X-ray on even more important stuff like nuclear plant welds ("China Syndrome" has nice depiction around it).

Re: XB-1's wings are officially closed out

#20

This is probably a dumb question, but if the wings are now closed forever, how does one do maintenance or inspection of the mechanical flight control systems composed of cables and pulleys? Is the expectation that the XB-1 is going to be used in flight for far less than the design life of those mechanical systems?

They probably use an electrified system with wiring and servos, levers and push rods. Prior to that we used hydraulics. These parts are probably accessible with removable panels.
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