Atmospheric Re-Entry

[Armitage]

Star Hero says an object making a controlled re-entry takes 5 BODY per segment from atmospheric friction.

What about an uncontrolled re-entry? The damage must be higher, otherwise meteors would plunge to Earth without a scratch.

Plus the old "We have to get the ship under control before we burn up in the atmosphere!!"

[Chris Goodwin]

Figure that to get an optimum reentry angle, the pilot has to make a Piloting roll with whatever penalties the GM sees fit. If the roll is critically failed, the ship breaks up right then and there, no need to go any further. If the roll is just failed, roll 1d6 to determine (1-3) whether the angle is too steep (the ship takes more damage) or (4-6) too shallow (the ship skips off the atmosphere). If the angle is too steep, the ship takes +1 BODY per Segment for every point the roll was missed by. The pilot can attempt another roll each Phase (perhaps with a penalty for each failed roll), but that opens up the possibility he will crit fail or at least fail worse.

 

Some ships have lots of bonuses to the pilot's roll.

[Aroooo]

All this of course is considered unpowered controlled re-entry (i.e. Apollo, the Space Shuttle). Futuristic ships will no doubt have powered re-entry, meaning they can enter the atmosphere at controlled velocities rather than a free fall.

 

Aroooo

[AlHazred]

So would the reentry be a Gliding power, or would you just handle it as a long, somewhat-controlled fall?

[Aroooo]

Originally posted by AlHazred

So would the reentry be a Gliding power, or would you just handle it as a long, somewhat-controlled fall?

 

I don't have FRED in front of me, so I can't re-read Gliding, but off the top of my head, I'd say the Shuttle def. has gliding. Apollo, Soyuz, not sure right now. I'll have to dig FRED out of the suitcase first. (Yes, I'm sad; I did bring FRED and SH on vacation with me )

 

Aroooo

[Nelijal]

Originally posted by AlHazred

So would the reentry be a Gliding power, or would you just handle it as a long, somewhat-controlled fall?

FREd p118 says "A gliding character has some control over his movement, but not the total control provided by Flight." FREd also gives hanggliding and parachuting as examples. Since the Space Shuttle maneuvers during reentry (S-turns to bleed airspeed) I would think Gliding applies to it. The earlier capsules followed a ballistic path with no means to alter their trajectory, and that sounds like a freefall to me.

 

It's a close call, I mean it's not like the shuttle can turn around and go the other way. In HERO terms, the Gliding power for reentry would require a heavy Limitation on how much control you have in maneuvering the vehicle.

[Aroooo]

I read the Gliding rules today too, and have to say I'd probably apply a -1 Gliding gains no altidude limitation for the Shuttle, since its too heavy to gain altitude from thermal updrafts.

 

Aroooo

[AlHazred]

Having reread the relevant section, I'd also give the Shuttle Limited Maneuveravbility to reflect its heavily decreased Turn Mode. It makes four S-turns to bleed off speed during the twenty minutes or so of descent; that sounds like 1 Turn per 5 Minutes to me.

 

If we treat all one-use booster sections of the Apollo spacecraft as 1 Fuel Charge OAFs, and consider only the Apollo capsule as a Vehicle, then it definitely has the same Gliding as a parachute - less than the Shuttle, but better than falling that distance.

[DarkGreen]

Originally posted by AlHazred

If we treat all one-use booster sections of the Apollo spacecraft as 1 Fuel Charge OAFs, and consider only the Apollo capsule as a Vehicle, then it definitely has the same Gliding as a parachute - less than the Shuttle, but better than falling that distance.

 

I never thought of handling booster rockets as OAFs (delicate and expensive as well). That's great.

 

-DG

[AlHazred]

Originally posted by DarkGreen

I never thought of handling booster rockets as OAFs (delicate and expensive as well). That's great.

 

There's a good discussion in The Ultimate Vehicle about what constitutes a Vehicle and what's just a Power Focus. I almost think Bob could have gone maybe a paragraph further in encouraging serious thought about how parts of a vehicle that aren't reusable should be Foci.