There’s a nice article over at space.com this morning about the Perseid meteor shower which will peak on Monday. It’s got a nice history of meteor showers, and a primer that explains the difference between meteoroid, meteor and meteorite. (The first is the rock out in space, the second is the flash it makes when it hits the atmosphere, and the third is what’s left to hit the ground, if anything).

This year’s Perseids should be very good, because we’re going through the core of the old comet, and the moon will be almost new, so it won’t provide too much light to distract. It’s unlikely to be as spectacular as the Leonids were last fall–that kind of event, with thousands an hour, is very rare, but it’s worth planning to get out of town anyway (away from the light) next Monday, and see one of nature’s celestial shows.

As can be seen in the comments section of the last post on this subject, David Perron remains skeptical of XCOR‘s ability to do a suborbital vehicle, let alone an orbital one. But Jeff Greason, head of the company, has provided a (characteristically) informed and polite response. It’s nice to let someone from the company speak for them directly.

We certainly are well aware of the X-15 and similar vehicles. Some of our consultants are old Dryden retirees who were around in those days. Doing our mission requires a propellant fraction of about 70-75% by mass. The Xerus design is wet wing, so the volume available for propellant storage internally is a bit higher than might at first be apparent.

We don’t release most of the details of what we’re doing not because we don’t know them, but because we’re well aware that the details will change during development. We don’t want to fall in to the all-too-common trap of feeling that we can’t change things because of PR pressure.

Certainly when we are approached by a serious investment prospect, we go through a due diligence process where our estimates on vehicle performance, subsystem masses, etc. are challenged. We believe we have good answers for those questions.

To pick one example, if you look at the X-15 structural weight, the high heat load caused by lengthy maximum heating flights at relatively low altitude, combined with a heat-sink TPS approach, required a high structural weight just to keep from melting. Initial results for a more modern insulating TPS approach for suborbital vehicles look more promising.

As for going to orbit — that’s a lot further down the road. I think it’s far more important for space startups to demonstrate *profit* than any particular level of performance. Private space development is seriously starved for capital — and the way you improve that is by establishing a track record of investors making money by investing in space companies.

Lastly, we are *well* aware of the regulatory issues raised by one of the posters above. One of the reasons for doing the EZ-Rocket demonstrator was to put some urgency behind some of the regulatory development we and others are working with the FAA. Lots to do yet, but so far, so good.

[Tuesday morning update]

For those interested, Bruce Hoult, who manned the XCOR booth at Oshkosh, provides some additional detail, in a post to sci.space.policy last night, responding to another newsgroup member’s (Mike Walsh) analysis of the Xerus.

The concept shown is a rocket airplane. A big advantage of a rocket airplane is that you don’t need the complicated inlet system of an aircraft and don’t have the corresponding weight of the turbo-machinery. The trade-off is that you really are not going to go very far before you run out of propellant.

The Xerus will have 3 – 4 minutes of fuel, not a terribly large increase in duration over the EZ-Rocket, but it will have rather more thrust (and fuel flow) to allow it to accelerate near-vertically to Mach 3.5 or so. It’s not optimized for distance, but could probably manage on the order of 500 miles or so on a different (lower) trajectory designed to set up a supersonic glide from high altitude.

XCOR should be well qualified and prepared to build the rocket propulsion system. I believe they said it is a scale-up of the engine used on the EZ-Rocket.

Current thinking seems to be 4 x 2000 lb engines. That’s four times larger than the EZ-Rocket engines. Note that XCOR has already built engines spanning more than a 20:1 range, and the same engineers built a 5000 lb engine at Rotary Rocket (and they own the rights to that work).

The drawing of the aircraft does not show much space for propellant storage. I assume it is pretty much all available.

It should be about 75% fuel at takeoff.

[He means propellant here–fuel plus oxidizer–ed]

I note that at least the first version has a pilot and one passenger. It is apparently not an X-Prize candidate.

The X-Prize is 1) a one-off, not a sustainable revenue stream like tourist rides, and 2) will probably have already been claimed by the time Xerus flies. In the event that it hasn’t been claimed I’m assured that there will be a way to squeeze a 3rd person in. 🙂

I would hazard a guess that the success of the concept depends on just how hard it is to design a supersonic aircraft that can make repeated trips out of and back into the atmosphere. The short travel time should limit thermal problems. I will guess that the heat sink of the vehicle will do the job.

The reentry speed is only about 1 km/second, so the heat load is about 1/50th of that for an orbital vehicle.

The drawing does not show any reaction control motors and I would guess that they would be needed to orient the craft for reentry.

XCOR already has 50 lb motors suitable for this application.

Just how much does it cost to develop this type of rocket airplane? My assumption would be more than required for a ballistic rocket. If I remember comments from XCOR people and some charts I saw earlier they were estimating $10 to $20 million.

The numbers I’ve been told are around $3m – $4m to get to flyable hardware, $10m to complete the test program necessary to get permission to fly paying passengers.

Mr. Greason later endorsed these comments.

As can be seen in the comments section of the last post on this subject, David Perron remains skeptical of XCOR‘s ability to do a suborbital vehicle, let alone an orbital one. But Jeff Greason, head of the company, has provided a (characteristically) informed and polite response. It’s nice to let someone from the company speak for them directly.

We certainly are well aware of the X-15 and similar vehicles. Some of our consultants are old Dryden retirees who were around in those days. Doing our mission requires a propellant fraction of about 70-75% by mass. The Xerus design is wet wing, so the volume available for propellant storage internally is a bit higher than might at first be apparent.

We don’t release most of the details of what we’re doing not because we don’t know them, but because we’re well aware that the details will change during development. We don’t want to fall in to the all-too-common trap of feeling that we can’t change things because of PR pressure.

Certainly when we are approached by a serious investment prospect, we go through a due diligence process where our estimates on vehicle performance, subsystem masses, etc. are challenged. We believe we have good answers for those questions.

To pick one example, if you look at the X-15 structural weight, the high heat load caused by lengthy maximum heating flights at relatively low altitude, combined with a heat-sink TPS approach, required a high structural weight just to keep from melting. Initial results for a more modern insulating TPS approach for suborbital vehicles look more promising.

As for going to orbit — that’s a lot further down the road. I think it’s far more important for space startups to demonstrate *profit* than any particular level of performance. Private space development is seriously starved for capital — and the way you improve that is by establishing a track record of investors making money by investing in space companies.

Lastly, we are *well* aware of the regulatory issues raised by one of the posters above. One of the reasons for doing the EZ-Rocket demonstrator was to put some urgency behind some of the regulatory development we and others are working with the FAA. Lots to do yet, but so far, so good.

[Tuesday morning update]

For those interested, Bruce Hoult, who manned the XCOR booth at Oshkosh, provides some additional detail, in a post to sci.space.policy last night, responding to another newsgroup member’s (Mike Walsh) analysis of the Xerus.

The concept shown is a rocket airplane. A big advantage of a rocket airplane is that you don’t need the complicated inlet system of an aircraft and don’t have the corresponding weight of the turbo-machinery. The trade-off is that you really are not going to go very far before you run out of propellant.

The Xerus will have 3 – 4 minutes of fuel, not a terribly large increase in duration over the EZ-Rocket, but it will have rather more thrust (and fuel flow) to allow it to accelerate near-vertically to Mach 3.5 or so. It’s not optimized for distance, but could probably manage on the order of 500 miles or so on a different (lower) trajectory designed to set up a supersonic glide from high altitude.

XCOR should be well qualified and prepared to build the rocket propulsion system. I believe they said it is a scale-up of the engine used on the EZ-Rocket.

Current thinking seems to be 4 x 2000 lb engines. That’s four times larger than the EZ-Rocket engines. Note that XCOR has already built engines spanning more than a 20:1 range, and the same engineers built a 5000 lb engine at Rotary Rocket (and they own the rights to that work).

The drawing of the aircraft does not show much space for propellant storage. I assume it is pretty much all available.

It should be about 75% fuel at takeoff.

[He means propellant here–fuel plus oxidizer–ed]

I note that at least the first version has a pilot and one passenger. It is apparently not an X-Prize candidate.

The X-Prize is 1) a one-off, not a sustainable revenue stream like tourist rides, and 2) will probably have already been claimed by the time Xerus flies. In the event that it hasn’t been claimed I’m assured that there will be a way to squeeze a 3rd person in. 🙂

I would hazard a guess that the success of the concept depends on just how hard it is to design a supersonic aircraft that can make repeated trips out of and back into the atmosphere. The short travel time should limit thermal problems. I will guess that the heat sink of the vehicle will do the job.

The reentry speed is only about 1 km/second, so the heat load is about 1/50th of that for an orbital vehicle.

The drawing does not show any reaction control motors and I would guess that they would be needed to orient the craft for reentry.

XCOR already has 50 lb motors suitable for this application.

Just how much does it cost to develop this type of rocket airplane? My assumption would be more than required for a ballistic rocket. If I remember comments from XCOR people and some charts I saw earlier they were estimating $10 to $20 million.

The numbers I’ve been told are around $3m – $4m to get to flyable hardware, $10m to complete the test program necessary to get permission to fly paying passengers.

Mr. Greason later endorsed these comments.

As can be seen in the comments section of the last post on this subject, David Perron remains skeptical of XCOR‘s ability to do a suborbital vehicle, let alone an orbital one. But Jeff Greason, head of the company, has provided a (characteristically) informed and polite response. It’s nice to let someone from the company speak for them directly.

We certainly are well aware of the X-15 and similar vehicles. Some of our consultants are old Dryden retirees who were around in those days. Doing our mission requires a propellant fraction of about 70-75% by mass. The Xerus design is wet wing, so the volume available for propellant storage internally is a bit higher than might at first be apparent.

We don’t release most of the details of what we’re doing not because we don’t know them, but because we’re well aware that the details will change during development. We don’t want to fall in to the all-too-common trap of feeling that we can’t change things because of PR pressure.

Certainly when we are approached by a serious investment prospect, we go through a due diligence process where our estimates on vehicle performance, subsystem masses, etc. are challenged. We believe we have good answers for those questions.

To pick one example, if you look at the X-15 structural weight, the high heat load caused by lengthy maximum heating flights at relatively low altitude, combined with a heat-sink TPS approach, required a high structural weight just to keep from melting. Initial results for a more modern insulating TPS approach for suborbital vehicles look more promising.

As for going to orbit — that’s a lot further down the road. I think it’s far more important for space startups to demonstrate *profit* than any particular level of performance. Private space development is seriously starved for capital — and the way you improve that is by establishing a track record of investors making money by investing in space companies.

Lastly, we are *well* aware of the regulatory issues raised by one of the posters above. One of the reasons for doing the EZ-Rocket demonstrator was to put some urgency behind some of the regulatory development we and others are working with the FAA. Lots to do yet, but so far, so good.

[Tuesday morning update]

For those interested, Bruce Hoult, who manned the XCOR booth at Oshkosh, provides some additional detail, in a post to sci.space.policy last night, responding to another newsgroup member’s (Mike Walsh) analysis of the Xerus.

The concept shown is a rocket airplane. A big advantage of a rocket airplane is that you don’t need the complicated inlet system of an aircraft and don’t have the corresponding weight of the turbo-machinery. The trade-off is that you really are not going to go very far before you run out of propellant.

The Xerus will have 3 – 4 minutes of fuel, not a terribly large increase in duration over the EZ-Rocket, but it will have rather more thrust (and fuel flow) to allow it to accelerate near-vertically to Mach 3.5 or so. It’s not optimized for distance, but could probably manage on the order of 500 miles or so on a different (lower) trajectory designed to set up a supersonic glide from high altitude.

XCOR should be well qualified and prepared to build the rocket propulsion system. I believe they said it is a scale-up of the engine used on the EZ-Rocket.

Current thinking seems to be 4 x 2000 lb engines. That’s four times larger than the EZ-Rocket engines. Note that XCOR has already built engines spanning more than a 20:1 range, and the same engineers built a 5000 lb engine at Rotary Rocket (and they own the rights to that work).

The drawing of the aircraft does not show much space for propellant storage. I assume it is pretty much all available.

It should be about 75% fuel at takeoff.

[He means propellant here–fuel plus oxidizer–ed]

I note that at least the first version has a pilot and one passenger. It is apparently not an X-Prize candidate.

The X-Prize is 1) a one-off, not a sustainable revenue stream like tourist rides, and 2) will probably have already been claimed by the time Xerus flies. In the event that it hasn’t been claimed I’m assured that there will be a way to squeeze a 3rd person in. 🙂

I would hazard a guess that the success of the concept depends on just how hard it is to design a supersonic aircraft that can make repeated trips out of and back into the atmosphere. The short travel time should limit thermal problems. I will guess that the heat sink of the vehicle will do the job.

The reentry speed is only about 1 km/second, so the heat load is about 1/50th of that for an orbital vehicle.

The drawing does not show any reaction control motors and I would guess that they would be needed to orient the craft for reentry.

XCOR already has 50 lb motors suitable for this application.

Just how much does it cost to develop this type of rocket airplane? My assumption would be more than required for a ballistic rocket. If I remember comments from XCOR people and some charts I saw earlier they were estimating $10 to $20 million.

The numbers I’ve been told are around $3m – $4m to get to flyable hardware, $10m to complete the test program necessary to get permission to fly paying passengers.

Mr. Greason later endorsed these comments.

Professor Reynolds approvingly quotes Professor Volokh (I’ve linked to Glenn’s site, because blogspot permalinks seem to be fubar lately):

By the way, note also that the Washington Post article mentioned below mentioned the “gun lobby.” I wonder: Would they have called NARAL and other groups on NARAL’s side of the issue the “abortion lobby”? Would they have called the Reporters’ Committee for Freedom of the Press the “press lobby”? Would they have called the NAACP the “black lobby”?

I somehow doubt it.

Me, too. As another example, I’ve commented in the past on the tendency of defenders of the War On (Some) Drugs to use an ad hominem attack, accusing (with no basis) proponents of more rational drug policies of being drug users, or drug user wannabes. As I’ve said in the past, it’s just as odious a tactic as accusing someone opposed to racial quotas of being a racist, as though it’s not possible for someone to take a stance on principle.

As Eugene points out, the media is quite selective in their labeling. If it’s a liberal/left cause, the group is an “X Rights group,” but if it’s perceived to be a “right-wing” cause, then the group is labeled an “X group” (no rights need be mentioned).

So, is, for example, the Drug Policy Alliance (formerly the Drug Policy Foundation) a civil rights group (defending the right of people to consume whatever vegetation they desire, and to not have their property invaded or appropriated without a trial), or a “drug use advocacy group”? They believe the former, but the drug warriors attack them as the latter.

A two-inch toy rifle, designed to be shouldered by a G.I. Joe doll, was confiscated at LAX.

A spokesman for Los Angeles International Airport said: “We have instructions to confiscate anything that looks like a weapon or a replica.”

“If GI Joe was carrying a replica then it had to be taken from him.”

I’m starting to wonder if the Bush Administration’s acquiescence in the federalization of airport security was a rope-a-dope ploy, knowing that imbecilities like this would eventually destroy all public support for it.

It’s actually a kind of gruesome story. I wonder if she was on top?

Jim Oberg posts:

A month ago, Lance Bass’s promoters purchased four weeks of spaceflight training for him, from the Gagarin Center at Star City (in a deal that Klimuk would sell to anybody for a price of about $100,000 or so). That training interval has now ended — there was supposed to be a zero-G airplane flight over the weekend, but no word that it happened. Last week, also, word from Moscow was that the Bass team needed to pay a first down payment of $1.5 million to continue preparing for the Soyuz mission in October. But as of the ‘final’ due date last Friday, there was no word except that maybe it would happen ‘next Monday’ (this, from CNN). There are no reports that it has happened today (Monday). Does this mean the money has run out, and all we have left are more promises? When — if ever — will we see any proof that the project can afford the REAL cost of the flight?

Time is running short, and it does appear, amidst all of the rumors, that the tactics are aimed at buying time. On the other hand, there have also been rumors that a second sponsor has been lined up, along with Radio Shack, to be announced today. We’ll see shortly.

The desire of the press to rehabilitate the Clinton Administration is apparently boundless. Now Reuters is reporting that the Bush transition team was given a plan to deal with Al Qaeda that the incoming administration ignored.

How is it that, if the Clinton Administration had such a wonderful plan, they weren’t implementing it themselves? Why were they waiting for the Bush Administration to come in?

This is Bravo Sierra.

Hey, anybody remember that nuclear war we were about to have in south Asia a few weeks ago? It’s not even on the media radar screen any more.