NASASpaceFlight.com Forum

General Discussion => Historical Spaceflight => Topic started by: Seer on 01/17/2011 07:29 PM

Title: Hotol 2
Post by: Seer on 01/17/2011 07:29 PM
Can someone explain why the air launched Hotol 2 needed 4 rd 0120 engines?
http://www.astronautix.com/lvs/inthotol.htm.  This gives an initial T/W ratio of over 3 which seems much too high.
Title: Re: Hotol 2
Post by: Joris on 01/20/2011 08:47 PM
It appears that the weight of HOTOL (250t) is less then that of MAKS (275t) according to encyclopedia astronautica. But HOTOL is longer (44m to 39m) and wider (10m to 6.38m). MAKS had a not extraordinary T/W of 1.4, so my guess is that the 250t weight of HOTOL is too low, since the thrust is higher and so is its size.
Title: Re: Hotol 2
Post by: Seer on 01/21/2011 04:07 PM
It appears that the weight of HOTOL (250t) is less then that of MAKS (275t) according to encyclopedia astronautica. But HOTOL is longer (44m to 39m) and wider (10m to 6.38m). MAKS had a not extraordinary T/W of 1.4, so my guess is that the 250t weight of HOTOL is too low, since the thrust is higher and so is its size.

No, the Maks length and diameter are smaller because it refers to a small winged orbiter plus external tank configuration.
Is it possible that two of the rd-0120 engines are in the an-225 plane?

I believe someone who might know the answer is a poster on this forum named Hempsell who works for Reaction engines. If he wants to chime in I'd be grateful.