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-   -   [Spaceships] Winged Spaceships (https://forums.sjgames.com/showthread.php?t=124899)

scc 04-12-2014 03:35 AM

[Spaceships] Winged Spaceships
 
OK, page 30 in Spaceships (The original, 4e one, Stock #37-0120), the section on Winged suggests that spaceships with wings get better performance in atmosphere, but I can't seem to find anything that backs this up.

So, question, am I reading too much into something or is there something I can't find or missing?

Phantasm 04-12-2014 03:59 AM

Re: [Spaceships] Winged Spaceships
 
The details for aerial performance are on p. 35 of the same book. The exact bonuses for wings are +4 to Hnd and +1 to SR.

Hope this helps.

scc 04-12-2014 04:30 AM

Re: [Spaceships] Winged Spaceships
 
Thanks. And no it doesn't, I was hopping for a speed boost or something. I may just end up using boosted performance chemical rockets (The ones in Spaceships are actually worse performers then the SSME's)

Phantasm 04-12-2014 05:01 AM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by scc (Post 1748648)
Thanks. And no it doesn't, I was hopping for a speed boost or something. I may just end up using boosted performance chemical rockets (The ones in Spaceships are actually worse performers then the SSME's)

Realistically, wings tend to reduce speed, not increase it. They're meant to provide lift and/or hardpoint mounts.

For example, look at the swing-wing feature on the F-14 Tomcat. It uses its wings in full extension during takeoff and landing, but when it shifts to supersonic flight it pulls its wings in closer to the body. The first situation gives more lift and greater drag due to having more of the wing edge exposed to the oncoming air. The second reduces drag and wing edge; the plane cuts through the air faster. If it tried to go supersonic with the wings extended, the wings would get pulled off from the air pressures at those velocities.

Indeed, some of the fastest fighter planes ever flown have almost no wing, but they also tended to have a very wide turning radius, making the slower but more maneuverable planes better at dogfighting.

For a smaller example, look at the speeds of dogfighting missiles compared to those of cruise missiles. Dogfighting missiles that have almost no wing (maneuvering flaps at best) have speeds of Mach 3+, while cruise missiles with a long wing are subsonic.

Clear as mud?

scc 04-12-2014 05:27 AM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by tbrock1031 (Post 1748652)
Realistically, wings tend to reduce speed, not increase it. They're meant to provide lift and/or hardpoint mounts.

For example, look at the swing-wing feature on the F-14 Tomcat. It uses its wings in full extension during takeoff and landing, but when it shifts to supersonic flight it pulls its wings in closer to the body. The first situation gives more lift and greater drag due to having more of the wing edge exposed to the oncoming air. The second reduces drag and wing edge; the plane cuts through the air faster. If it tried to go supersonic with the wings extended, the wings would get pulled off from the air pressures at those velocities.

Indeed, some of the fastest fighter planes ever flown have almost no wing, but they also tended to have a very wide turning radius, making the slower but more maneuverable planes better at dogfighting.

For a smaller example, look at the speeds of dogfighting missiles compared to those of cruise missiles. Dogfighting missiles that have almost no wing (maneuvering flaps at best) have speeds of Mach 3+, while cruise missiles with a long wing are subsonic.

Clear as mud?

Clear (as soup). But given that I'm looking for altitude before lighting of my rockets, does the extra lift wings provide help? Enough to be noticeable?

And are there rules for things like ram and scram jets in something somewhere for Spaceships? Or any other high altitude propulsion systems?

(And who decided that ram rocket Nuclear Thermal Rockets would work without super-science?)

vicky_molokh 04-12-2014 08:15 AM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by scc (Post 1748655)
Clear (as soup). But given that I'm looking for altitude before lighting of my rockets, does the extra lift wings provide help? Enough to be noticeable?

And are there rules for things like ram and scram jets in something somewhere for Spaceships? Or any other high altitude propulsion systems?

(And who decided that ram rocket Nuclear Thermal Rockets would work without super-science?)

Check out Getting into Space on SS1:37 and Atmospheric Landings on SS1:40.

vierasmarius 04-12-2014 08:44 AM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by scc (Post 1748655)
And are there rules for things like ram and scram jets in something somewhere for Spaceships? Or any other high altitude propulsion systems?

Spaceships doesn't go into very much detail on the specifics of its propulsion systems. The basic Jet Engines are actually turbo ramjets or scramjets, functioning in a minimum of 0.1 atmos with no limit on top speed.

Ulzgoroth 04-12-2014 09:56 AM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by scc (Post 1748655)
Clear (as soup). But given that I'm looking for altitude before lighting of my rockets, does the extra lift wings provide help? Enough to be noticeable?

Altitude is totally overlooked by Spaceships, and even realistically isn't that important. The main challenge of getting to orbit is getting orbital velocity up. An airbreathing engine lets you get some of that at very favorable rates for the fuel mass. Wings do help there in that they allow your vessel to fly if it doesn't have thrust exceeding gravity.

Wings are most useful for landing, though. They impose no weight penalty unlike a Soft-Landing System (in the rules, not reality) and allow you to use aerodynamic landing (easier and requiring no fuel) rather than having to pull off a vertical powered landing.
Quote:

Originally Posted by scc (Post 1748655)
And are there rules for things like ram and scram jets in something somewhere for Spaceships? Or any other high altitude propulsion systems?

As vierasmarius notes, the basic jets are those. ("turbo ramjet or scramjet", from the book.) Spaceships 7 has a 'turbofan' alternative that isn't capable of arbitrarily high speed.
Quote:

Originally Posted by scc (Post 1748655)
(And who decided that ram rocket Nuclear Thermal Rockets would work without super-science?)

Uh. Tons of people? Like, Project Pluto plus a huge number of old-time futurist types talking about nuclear-powered airplanes and such. Why would you say they can't?

Anthony 04-12-2014 01:44 PM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by scc (Post 1748648)
Thanks. And no it doesn't, I was hopping for a speed boost or something. I may just end up using boosted performance chemical rockets (The ones in Spaceships are actually worse performers then the SSME's)

0.15 mps delta-V for a 5% mass fraction corresponds to an ISp of about 490, which is significantly better than the SSME.

scc 04-12-2014 03:27 PM

Re: [Spaceships] Winged Spaceships
 
Quote:

Originally Posted by Anthony (Post 1748729)
0.15 mps delta-V for a 5% mass fraction corresponds to an ISp of about 490, which is significantly better than the SSME.

There's a formula provided in the designers notes, ISp/3,000 = mps and .05 times thrust-to-weight ratio = thrust for Spaceships, the SSME has values of ISp 452.3 and 65.91, this gives the SSME .1507 then a line of 6's for mps per tank and 3.2955 G for accel.

As for NTR ram rockets, there was research into them in the 50's and early 60's. The Russian's actually got a plane off the ground using them. They did this by removing most if not all shielding from the reactor and using a Direct Air Cycle system, the words environmental disaster spring to mind.


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