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Paul Allen's new rocket-launching plane

arstechnica.com

11–20 of 170 posts

Re: Paul Allen's new rocket-launching plane

#11

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

[deleted]

Re: Paul Allen's new rocket-launching plane

#12

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

If you read a bit more carefully you'll see that the previous record holder was the Spruce Goose

Re: Paul Allen's new rocket-launching plane

#13

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

> previous record by 65 feet

Re: Paul Allen's new rocket-launching plane

#14

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

It beats the previous record by a margin of 65 feet, I believe.

Re: Paul Allen's new rocket-launching plane

#15

I'm confused as to what this thing can accomplish. It can probably fly very high, but I assume it can't fly very fast (relative to orbital speed), and I thought the overwhelming majority of the delta-V to get something into orbit was for forward momentum and that just launching from higher up wouldn't help much. Clearly there's something I'm missing here (or they wouldn't have built it), can anyone fill me in?

From wikipedia [1]:

>Atmospheric and gravity drag associated with launch typically adds 1.3–1.8 km/s to the launch vehicle delta-v required to reach normal LEO orbital velocity of around 7.8 km/s (28,080 km/h).

So it'll help. Also significant is the ability to base out of an airport and launch closer to the equator.

[1] https://en.wikipedia.org/wiki/Low_Earth_orbit

Re: Paul Allen's new rocket-launching plane

#16

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

[deleted]

Re: Paul Allen's new rocket-launching plane

#17

I'm confused as to what this thing can accomplish. It can probably fly very high, but I assume it can't fly very fast (relative to orbital speed), and I thought the overwhelming majority of the delta-V to get something into orbit was for forward momentum and that just launching from higher up wouldn't help much. Clearly there's something I'm missing here (or they wouldn't have built it), can anyone fill me in?

Checkout the photo gallery, it seems to launch a rocket from between the two hulls while flying very high in the atmosphere (less drag and gravity).

[deleted]

Re: Paul Allen's new rocket-launching plane

#18

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

Blows past the previous record by 65 ft. The Spruce Goose[0] had a wingspan of 320 ft.

(It's possible the article has been updated since you saw it to correct that.)

[0] https://en.wikipedia.org/wiki/Hughes_H-4_Hercules

Re: Paul Allen's new rocket-launching plane

#19

The article claims that it hold's the record for largest wingspan, which is 385ft. It then goes on to say that this blows away the previous record of 65ft. I don't know what the largest wingspan is, but I thought B-52s had a wingspan of 185ft? Error in the article?

Thank you all. My mistake. Much embarrass.

Re: Paul Allen's new rocket-launching plane

#20

I'm confused as to what this thing can accomplish. It can probably fly very high, but I assume it can't fly very fast (relative to orbital speed), and I thought the overwhelming majority of the delta-V to get something into orbit was for forward momentum and that just launching from higher up wouldn't help much. Clearly there's something I'm missing here (or they wouldn't have built it), can anyone fill me in?

From wikipedia [1]: >Atmospheric and gravity drag associated with launch typically adds 1.3–1.8 km/s to the launch vehicle delta-v required to reach normal LEO orbital velocity of around 7.8 km/s (28,080 km/h). So it'll help. Also significant is the ability to base out of an airport and launch closer to the equator. [1] https://en.wikipedia.org/wiki/Low_Earth_orbit

Combine that with the tyranny of the rocket equation and it becomes sensible.
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