Latest News from DaVinci

The media briefing should be starting now and the roll out later in the afternoon.

mmm.... rubbing my hands in anticipation.

AH! Can't wait! Do we know when the announcement will be made? At the media conference, or would they wait for during the public showing??
- binarysunrise

The most detailed information on WF6 can be found on DaVinci's site under the Technical tab -- Vehicle subtab in a file called "da Vinci Space Project Mission Analysis(pdf)". Essentially everything else on their site is about the prototype, WF2.

It's interesting to note that in the PDF file, there are two photos shown related to the new Hybrid engine -- a test firing and a shot of the nozzle. Both of these photos came from eAC's site (http://www.hybrids.com), i.e. the firm that lost the bid to make SS1's engine.

However -- the photos came from eAc's 'Hyperion II' project. This is a small (12" diameter) suborbital sounding rocket, and the engine is not in a class to work for WF6. It produces 5,000 pounds of thrust, whereas DaVinci's PDF file indicates 15,000 lbs. I searched eAc's site for an engine in the 15,000 lb class, but was unable to locate such. Even the engine they made for SS1 developed only a bit over 10,000 lbs.

How do you launch a rocket from a balloon? Has anybody ever tried it?

[quote="mrmorris"]It's interesting to note that in the PDF file, there are two photos shown related to the new Hybrid engine -- a test firing and a shot of the nozzle. Both of these photos came from eAC's site (http://www.hybrids.com), i.e. the firm that lost the bid to make SS1's engine.[quote]

Perhaps eAC is Da Vinci's engine supplier? Wouldn't the engine for WildFire actually not need as much thrust as SS1's engine? I mean, it launches from nearly twice the altitude, and SS1's engine is lit when it's flying nearly horizontal, both of which would give WildFire a head start on spaceshipone. Maybe Da Vinci will end up using the engine that Scaled turned down.

The nitrous tank and the case/throat/nozzle assembly on the SS1 engine were developed internally by Scaled, and Spacedev and eAc worked on the internal components (ignitor, fuel grain, etc.) . So if eAc internals from their SS1 engine are being used on the DaVinci engine, then a nitrous tank and case/nozzle similar to (but not necessarily identical to) the Scaled ones have to come from somewhere. eAc wouldn't transfer Scaled-developed engine technology to DaVinci, since it's probably forbidden under their contract with Scaled and doing so would be grounds for a lawsuit from Scaled.

This means DaVinci would have to develop a tank and case/nozzle similar to the Scaled ones on their own if they want to use internals from eAc's SS1 engine, or DaVinci's engine is simply an enlargement of the Hyperion II engine which comes from eAc exclusively (and is developed from the earlier Hyperion I). This would explain the Hyperion II pictures in DaVinci's paper...

I believe a few small rocket companies and amateur teams have tried to launch some small rockets from a balloon. One of them is Harc: an Xprize team. Here's a link to their webpage about balloon launches:
http://www.harcspace.com/balloon.php

Here's what happened to HARC when they tried for the CATS (Cheap Access to Space) Prize in 2000 (250 grand for launching 2 kg to 200 km). It didn't work out so good:

http://www.wired.com/news/technology/0, ... 65,00.html

Here are a coujple other links that talk about balloon-launched rockets:

http://www.astronautix.com/lvs/rockoon.htm

http://fly.hiwaay.net/~bbrown/rockoon.htm

I'm not sure anyone's ever tried to launch something nearly this big from a rocket before tho.

payloads this large have been carried before, but nothing this big has been launched from a balloon before. I'm most worried about the recoil that the balloon will have to take in as the rocket launches... would the balloon not rip from that much force? I guess we'll see, but I wish them the best of luck!

I don't know if this is the case, but couldn't Da Vinci just drop the craft, so it could launch its engines while in free fall?

You would have to have balls if you were gonna fire the engines in a freefall,the rocket would have to be well balanced,cause if it started to tumble...........You would have to have more control over it in a free fall as more things are gonna happen and with no wings like a plane your gonna have fun controling it initially!!!

Iain

There are fewer aerodynamic surfaces to cause anomalies during the drop period.