Hypersonic suborbital aircraft design quandary

[madmike]

This one has stumped me a bit.

There seems to be no provision for hypersonic suborbital type aircraft design in the Vehicles supplement that does not involve applying multiples of increase speed mods. If I stuck to supersonic, then I would have no real issues, but I have a specific design in mind.

Range is an issue as well as such aircraft climb up into the very upper atmosphere and descend at high speeds. So maximum range is significantly further than the 7000km base + Increased range mods can provide.

I can get a design out, but the cost is enormous and certainly not economical, either in the now or four hundred years in the future.

So I am open to any thoughts to solving this quandary!

[hiro]

As you can't design a hypersonic grav vehicle any easier than you can a hypersonic aircraft it seems to me the rules need a little modding. As they stand the max speed I can see a TL8 aircraft achieving is 3200km/h which the X-15 more than doubled back in the 60s and with some of the current X planes being the forerunners to what you're trying to design it seems that the rules have a bit of a gap.

I'd house rule it and add a hypersonic modification to the light and heavy jet chassis types setting the speed multiplier and cost linked to TL.

Alternatively, have you tried designing a sub orbital hypersonic aircraft using the small craft rules in High Guard?

[madmike]

It seems I will be creating my own chassis specs for this.

Thanks Hiro. You are echoing my thought processes regarding this issue.

[ShawnDriscoll]

This one has stumped me a bit.

There seems to be no provision for hypersonic suborbital type aircraft design in the Vehicles supplement that does not involve applying multiples of increase speed mods. If I stuck to supersonic, then I would have no real issues, but I have a specific design in mind.

Range is an issue as well as such aircraft climb up into the very upper atmosphere and descend at high speeds. So maximum range is significantly further than the 7000km base + Increased range mods can provide.

I can get a design out, but the cost is enormous and certainly not economical, either in the now or four hundred years in the future.

So I am open to any thoughts to solving this quandary!

Sounds like you're trying to make vehicles from our universe instead of from Traveller's. If it's not mentioned in the book, it probably doesn't exist in Traveller.

[madmike]

Really? A hypersonic atmospheric vehicle does not exist in Traveller? Good Lord. I have been playing this game and designing vehicles in this game for 35 years.

This is the first time someone has told me that it cannot exist within Traveller because it is NOT mentioned in a design book.

Simply amazing.

[Rikki Tikki Traveller]

Definitely a new chassis design - after all a Hypersonic craft will have to be a special hull. Normal aircraft hulls, even supersonic hulls, will not work at those speeds.

Good thing the design rules are OGL, so you can even publish it!

[hiro]

It seems I will be creating my own chassis specs for this.

Have you tried using the small craft sequence from High Guard?

I've skimmed the rules but not committed anything to paper as I'm not that familiar with the design sequence, tho it looks achievable.

[phavoc]

I would say range for any sub-orbital aircraft (not spacecraft) is effectively unlimited, insofar as it's taking a one-way trip. Once it reaches a certain height it essentially glides it's way around the globe till it starts a descent.

The question for range becomes one of fuel though. Sure, it could circumnavigate the globe (say 12,000km), but that wouldn't necessarily mean it could do 4 3,000km hops because of how it flies.

So it would be tricky to list range unless you devise a house rule to accommodate.

For the most part once grav tech comes around it should be much cheaper to buy one off planet, and use it's anti-grav capability to make the same flight trajectory. The difference of course is going to be speed. Hypersonic non-G capable craft is going to be the pants off any standard anti-grav ship in time to destination.

[madmike]

Thanks all

I elected to go the new chassis route with the specifications I needed.

[Colin]

Originally, there had been a "hypersonic" mod for Jet Aircraft Chassis. but I coldn't make it work out how I wanted. I didn't use a separate chassis, though that works too. My version had a mod that boosted speed and range, at the expense of space and cost. I wouldn't mind seeing your "hypersonic" chassis, though.

[madmike]

Thanks for that info Colin

I have designed a HST using my chassis design and after a bit of tweaking to it, seems to work well.

Cost comes out around the same price as a small starship, so that is about right too.

[hiro]

Mike, would you care to share or is it to be part of a future publication?

[madmike]

Hiro, it is part of a future publication, so I will not freely release it at this stage.

[hiro]

Understood. Let us know which one it is when you're able.