But this IS my idea of relaxation!

[kaigou]

For a takeoff using pure thrust and no wings, the thrust-weight ratio for the vehicle has to be more than one (for launch from the Earth's surface, for launch from the Moon it only needs to be more than 0.1654). In general, the thrust-to-weight ratio is numerically equal to the g-force that the vehicle can pull, provided the g-force exceeds local gravity then takeoff can occur. [Definition via Wikipedia.]

designation / name	series or country	length (m)	wt, emp (ton)	wt, gross (ton)	thrust (kN)	T/W ratio
RX-78-2 Gundam	MSG	18.5	43.4	60.0		0.93
RX-78GP01 Zephyranthes	0083	18.5	39.7	65.0		1.66
RX-178 Mark II	Zeta	19.6	33.4	54.1		1.50
F91 Gundam	F91	15.2	7.2	19.9		4.44
XXXG-00W0 Wing Zero	W	16.7	8.0	?		?
GT-9600 Leopard	X	16.8	8.5	?		?
WD-M01 Turn-A	Turn-A	20.0	17.5	28.6		?
GAT-X105 Strike	SEED	17.7	?	64.8		?
GN-001 Exia	00	18.3	57.2	?		?
Typhoon F2	UK	15.9	11.0	15.6	60.0	1.18
F-35 Lightning	US	15.4	11.7	20.1		0.89
F-22 Raptor	US	18.9	14.3	25.1		1.26
F-20 Tigershark	US	14.2	5.0	6.8		1.13
Kfir C-2	Israel	15.6	7.3	10.4	52.9
MiG-23MLD Flogger-L	USSR	16.7	9.5	15.7		0.88
F-89D Scorpion	US	16.4	11.0	19.2	24.9	0.35
F-117 Night Hawk	US	20.0	13.4	23.8		0.40
B-2 Spirit	US	20.9	71.7	152.6		0.20

...In other words, I am such a frickin' geek.

Comments

[kaigou.livejournal.com]

I'm not entirely certain that propulsion no longer is an issue: if an object is going to move, it is either dragged, pushed, pulled, but in some way propelled. Even maglev trains -- which operate thanks to the repulsive power of two energized magnets, in simple terms -- still have rated/measureable propulsion (though I guess that'd be repulsion, technically?)...

My current theory about the overall weight of the mobile suits is that the designers are possibly riffing off the current theories/working knowledge of hybrid vehicles. A fighter jet carries a certain payload of armaments, but this is limited based on several things: the curb weight of the jet, the intended thrust-ratio (I've read of jets that got sent back to the drawing board when the t/w ratio, fully loaded, would end up lower unless weight got cut somewhere), and the weight of the fuel that has to be carried to allow the jet a specific range.

Now, the first problem is that currently our most common technology for engines is combustion, which requires fuel + oxygen + spark. We could run cars off batteries, but the drawback is that lacking combustion, the car would be like many electrical trains: sure, it'll get up to speed, but it doesn't have a lot of spunk. Those older battery-operated cars were so slow off the green light that drivers got frustrated and didn't want to have anything to do with them, and in a fighter jet (or mobile suit), you need explosive, abrupt, versatile power to maneuver in a dogfight. Natch.

Which means, I'd think, that any engine operating via stored batteries (which in and of themselves probably are a significant payload, possibly even heavier than fuel -- because as fuel burns up, the aircraft gets lighter, but batteries go empty but remain the same weight, which may even the t/w ratio throughout a flight, whereas conventional aircraft have t/w ratios that vary from starting/full to ending/empty) -- would be not only heavier due to batteries, but also heavier due to the additional engine adaptations required to modify an electrical engine so it can mimic the intense compression we get easily from a combustion engine.

Except that right now I should be dealing with painting the dining room ceiling instead of rambling on like this. Le sigh, I don' wanna... because OMG my brain is so happy when anyone makes a reply like yours. Don't mind me. This is my nirvana.