Virgin Orbit

[Beati Dogu]

They've been busy doing his speed taxi-runs with the 70 foot long rocket attached at Long Beach Airport in California.









Kinda cool, even if the very similar Pegasus rocket has been around since 1990 & is still in use:

https://www.youtube.com/watch?v=Bla3RsVia9A

Pegasus is smaller and is launched from a modified Lockheed Tristar.

[Eric Mc]

Pegasus is a LOT smaller - and 30 year old technology now.

I had a good chat with the Virgin Orbital chap at the Farnborough Airshow this year.

Might be worth a trip to Newquay Airport (RAF St Mawgan) when they finally get up and running.

[Beati Dogu]

Interesting. Unlike Pegasus, LauncherOne is a liquid fuelled rocket (RP-1/LOX) and should be a lot cheaper ("less than US$12 million")


Virgin Orbit did the first flight test with the rocket attached the other day.

https://www.youtube.com/watch?v=w7Z8nDShFes

It certainly looks the part.

[MartG]

Article on the carry test

https://www.spaceflightinsider.com/missions/commer...

[Beati Dogu]

They took it up to operational altitude on Monday - around 35,000 feet.

Apparently they flew at nearly 700 mph, or Mach 0.9 as well, which is pretty impressive; But then the 747 is.

[Eric Mc]

The 747 was designed for a high subsonic cruise speed. That is why it has such sharply swept wings (37.5 degrees) At the time the 747 was being designed (1966 to 1968), it was expected that ten years after entry into service (i.e. 1979/80), 747 operators would also be in the market for supersonic airliners and they wanted the 747 to be able to compete (after a fashion).

In the event, the lack of demand for supersonic airliners and the oil crisis of 1973 meant that 747 operators never flew their 747s at these higher speeds, being more interested in fuel economy.

Nice to see that its speed capability has finally found a practical use.

[Toaster]

Beati Dogu said:

They took it up to operational altitude on Monday - around 35,000 feet.

Apparently they flew at nearly 700 mph, or Mach 0.9 as well, which is pretty impressive; But then the 747 is.

The spitfire was pretty impressive too in 1943 one flew at Mach 0.89, Then another in 1944 one flew at Mach 0.92but the propellor fell off !

Although the guinness book of records states that the fastest propellor plane is the is the XF-84H Thunderscreech with a speed of Mach 0.83 in 1997

You guys are easily impressed even a DC10 can fly at 610 MPH The sound barrier is the tricky bit up to the speed of sound its not that difficult

Edited by Toaster on Friday 7th December 23:50

[Eric Mc]

Toaster said:

The spitfire was pretty impressive too in 1943 one flew at Mach 0.89, Then another in 1944 one flew at Mach 0.92but the propellor fell off !

Although the guinness book of records states that the fastest propellor plane is the is the XF-84H Thunderscreech with a speed of Mach 0.83 in 1997

You guys are easily impressed even a DC10 can fly at 610 MPH The sound barrier is the tricky bit up to the speed of sound its not that difficult

Edited by Toaster on Friday 7th December 23:50

I can guarantee that no XF-84H ever did anything in 1997 - apart from standing motionless in a museum.

The point remains that the 747 was designed for a fairly high subsonsic cruise number for the reasons mentioned above. It never exploited that speed capability in airline services because the nature of airline flying changed just as the 747 was beginning to enter the market.

This speed capability can now be used in this new role as a satellite launcher.

[Toaster]

Eric Mc said:

I can guarantee that no XF-84H ever did anything in 1997 - apart from standing motionless in a museum.

The point remains that the 747 was designed for a fairly high subsonsic cruise number for the reasons mentioned above. It never exploited that speed capability in airline services because the nature of airline flying changed just as the 747 was beginning to enter the market.

This speed capability can now be used in this new role as a satellite launcher.

Phew at least you didn't disrespect the Spitfire, that would be a hanging offence lol, I will concede I got the XF-84H wrong but it did have a predicted design speed

Then it must be the Ruskies with the former Soviet Tu-95/142 which is the fastest propeller-driven aircraft in standard production form, with a maximum level speed of Mach 0.82

As far as the 747 is concerned and to most if not all public transport for longevity and economy so its not that special just unusual although I bet the Military versions will put the peddle to the metal when its something urgent like getting a president somewhere on time lol.

[Eric Mc]

Peddle?

Military 747s (there have never been that many military 747s) are generally flown at more or less the same types of cruise speeds as their civilian counterparts.

I think the use of the high Mach cruise numbers is a bit of a bonus for the Virgin Orbit team. I'm not sure what the highest Mach number available to the L1011 is (as used for Pegasus launches) but I don't think it's as high.

[Einion Yrth]

Eric Mc said:

Peddle?



I think the use of the high Mach cruise numbers is a bit of a bonus for the Virgin Orbit team. I'm not sure what the highest Mach number available to the L1011 is (as used for Pegasus launches) but I don't think it's as high.

In both cases it's a very long way shy of seven and a half kilometers a second, so how much difference does it make, really?

[Eric Mc]

Not a lot, I expect - but every little helps (as they say in the Asda ad).

[MartG]

It's not so much the speed as the altitude

The only reason rockets take off vertically is to get above the dense atmosphere as quickly as possible - they then turn to accelerate in the direction they need to be going to enter orbit i.e. horizontally

Launching from an aircraft at 30,000ft they are above a sizeable proportion of the atmosphere so can begin accelerating horizontally immediately after launch

[Eric Mc]

There are other advantages too - like getting above bad weather and being able to shift the launch site if required.

The big disadvantage is the smaller sizes of the boosters that can be lifted by an aircraft and consequently, the reduction in size and weight of the payload.

Obviously, with the advent of lightweight cubesats etc this is becoming less of an issue and the use of bigger and bigger aircraft (like the 747 and the Stratolauncher) will allow bigger boosters to be carried aloft.

[Beati Dogu]

MartG said:

Launching from an aircraft at 30,000ft they are above a sizeable proportion of the atmosphere so can begin accelerating horizontally immediately after launch

It seems they plan to pull the aircraft into a steep climb before they launch the rocket.

The first test launch will be early next year.

[Beati Dogu]

First drop test carried out over the range at Edwards AFB, California.



The rocket was inert and crashed into the desert.

It's always a relief when a new bit of kit doesn't actually take out the launch aircraft:

https://www.youtube.com/watch?v=fPTnmZ_HPAs

[Toaster]

Beati Dogu said:

First drop test carried out over the range at Edwards AFB, California.



The rocket was inert and crashed into the desert.

It's always a relief when a new bit of kit doesn't actually take out the launch aircraft:

https://www.youtube.com/watch?v=fPTnmZ_HPAs

So from a Science perspective what was learnt from this 'experiment', object dropped from plane....falls to earth. Oh I know... I can see the paper headlines now. 'Newtons law of Gravitation confirmed'

[eharding]

Toaster said:

So from a Science perspective what was learnt from this 'experiment', object dropped from plane....falls to earth. Oh I know... I can see the paper headlines now. 'Newtons law of Gravitation confirmed'

To be honest mate, you're getting a bit sad and tedious with this whole "Space Rockets Don't Belong In The Science Forum" schtick.

Here's a suggestion. The next time you see a space rocket themed post in here, and your OCD goes hyper OC, open up a Javascript console in your browser and paste this into it:

$("body").children().each(function () {
$(this).html( $(this).html().replace(/Science!/g,"Science and Space Rockets!") );
});



There you go. This is now the "Science and Space Rockets!" forum, your OCD is assuaged, and we all live happily ever after.

[Toaster]

eharding said:

Toaster said:

So from a Science perspective what was learnt from this 'experiment', object dropped from plane....falls to earth. Oh I know... I can see the paper headlines now. 'Newtons law of Gravitation confirmed'

To be honest mate, you're getting a bit sad and tedious with this whole "Space Rockets Don't Belong In The Science Forum" schtick.

Here's a suggestion. The next time you see a space rocket themed post in here, and your OCD goes hyper OC, open up a Javascript console in your browser and paste this into it:

$("body").children().each(function () {
$(this).html( $(this).html().replace(/Science!/g,"Science and Space Rockets!") );
});



There you go. This is now the "Science and Space Rockets!" forum, your OCD is assuaged, and we all live happily ever after.

To be honest 'Mate' you response is typical of a non scientist.

if you wished to discuss the the trajectories of a projectile with airdrop along with initial varying velocities it would be worthy of discussion within a science thread. As would displacement of parabolic throwing

Most of the threads regarding Rockets are oooooh, WOW, look at that... but nowt Science debate very little Science discussion Its like the Dark ages.

[Gojira]

eharding said:

Toaster said:

So from a Science perspective what was learnt from this 'experiment', object dropped from plane....falls to earth. Oh I know... I can see the paper headlines now. 'Newtons law of Gravitation confirmed'

To be honest mate, you're getting a bit sad and tedious with this whole "Space Rockets Don't Belong In The Science Forum" schtick.

Here's a suggestion. The next time you see a space rocket themed post in here, and your OCD goes hyper OC, open up a Javascript console in your browser and paste this into it:

$("body").children().each(function () {
$(this).html( $(this).html().replace(/Science!/g,"Science and Space Rockets!") );
});



There you go. This is now the "Science and Space Rockets!" forum, your OCD is assuaged, and we all live happily ever after.

Well said!

And politer than I would have been, too!