mk55 engine given some love!!!

[Ikaneko]

In 0.90, one of the changes was a bump to isp and gimbal range for the mk55.

I welcome this as most of my early mun landers use this engine.

It might also help end mk55 engine prejudice!!

(source)

[Slam_Jones]

Huh, as someone who's never used the mk55 before (due to how bad it used to be) I'll have to give it a try now!

[Frank_G]

Thank you for pointing there!

[Bill Phil]

Now it's good for OMS pods! I'm glad they buffed it, it really needed it.

[Rithsom]

Why didn't Squad buff this poor engine a long time ago? The Isp was just horrible.

[montyben101]

Now squad needs to make an SSME and space shuttles with be much easier!

[Temeter]

Still too heavy and not efficient enough. :/

[CalculusWarrior]

I believe the radial engines are purposely weaker than the inline engines so that players don't just slap more engines onto a lander to improve performance, they need to design it properly. Still, it's nice to see that the engine has received some love; it makes it more viable for designs.

[Rolanvorxariat]

Ahh... I felt like there was something weird about the radial engines-mainly the fact that I had half my fuel left after landing my mun base core. I thought it was just me. Good thing this got a bump. Extra fuel for return vehicles.

[Red Iron Crown]

I like the aesthetics of the Mk55 but hated its performance, this is a much needed buff.

[zekes]

Now squad needs to make an SSME and space shuttles with be much easier!

i just use the KR-2L as an SSME - it's efficient and big.

[Empiro]

This engine is pretty awesome now. I actually thought it was an OK engine before -- as a radial engine, you trade off ISP for convenience. It used it on my Duna lander to carry a large rover underneath.

[LABHOUSE]

I like the aesthetics of the Mk55 but hated its performance, this is a much needed buff.

Who cares about performance?! Only aesthetics and a twr of atleast 1 for the entire ship if a rocket matter!

[Rakaydos]

Hmm... it now has the same ISP and TWR as a LV45, with a better gimbal range, and it's drag doubles as tailfins.

[rodion]

i just use the KR-2L as an SSME - it's efficient and big.

well, most people don't make their shuttles 2,000 tons.

[moogoob]

Nice! This was on my unwritten "engines I never use and want to use again soon" list. The LTV-1 "Ant" engine was on there until recently when I made the tiniest Minmus lander ever.

[QuesoExplosivo]

Hey, I use the KR-2L for my 216 ton shuttle.

[King Arthur]

Just saying, the KR-2L is a relatively poor choice for an SSME when you consider its abysmal ISP at sea level.

[Renegrade]

Nice! This was on my unwritten "engines I never use and want to use again soon" list. The LTV-1 "Ant" engine was on there until recently when I made the tiniest Minmus lander ever.

They kinda overbuffed that one, I got a lot of mileage out of the ant for small probes even when it had 1.5kn of thrust (ex. lightweight RemoteTech sat-to-sat relays).

I do hope they get around to the 24-77 someday.

Just saying, the KR-2L is a relatively poor choice for an SSME when you consider its abysmal ISP at sea level.

Atmospheric specific impulse matters very little as most of the ascent is basically in a near-vacuum. At 8km, the KR-2L crosses past Mainsail vacuum performance, and at 12km, Skipper/T30/T45 vacuum performance. At 23km, it's basically in a hard vacuum. (at 3000m, it's already past the sea level performance of most other engines)

Combine that with the fact that it has a better TWR than any other non-solid engine, and you end up with a craft that's lighter overall, carrying less fuel and engine (assuming the payload's above a certain size) than other designs.

[lajoswinkler]

This thing???

I can barely look at it. Surely one of the ugliest parts in the game, and I'm a functionalist.

[Francois424]

Excellent news, this has been one of my favorite engine since I started playing.

As I learned more about ISP and fuel I had switched to Aerospikes for the 388 isp.

Now it's back on tracks, and time to use these for space shuttle operations.

Hopefully the Gimbal will be enough now (I doubt it, but gonna try)

[Madrias]

Hmm... Could be good news for one of my 0.22 based SSTO's. Evil little thing used an air-hogged turbojet to scream to high altitude, then fired off a pair of those MK55 Radials strapped to the wings just before flameout on the jet. Horrible fuel efficiency, but for a crew shuttle, it was great. Most of the time, it was just doing crew transfer to the Station, or to interplanetary ships, so it only had to make a 120 or 150 km orbit. It'd circularize on the 55's, rendezvous with RCS fuel, stop at the station to pick up some rocket gas and drop off crew, pick up any crew to be returned to Kerbin, and blast off for home, consuming the entire quantity of rocket fuel in a desperate bid to guarantee a lower-than-35km periapsis. Then it was a return to home factor on the jet engine, which had plenty of fuel left.

It also meant I had plenty of work to do with dropping off and exchanging gas tanks, which meant I always had something to do in my space program. Transfer crew, crew return to Kerbin, launch Minmus base, send shuttles of crew, rotate station crew, send up gas tanker to replace empty Rockomax Orange with full Rockomax Orange, return empty tank to Kerbin for recycling, and so on. Those ships consumed fuel rather well, though I found myself switching to alternate engines often enough because those radials were incapable of the 200 km orbit circularization needed when I started making heavier motherships. Was a bit more picky back then, that 120 km was my stations, 150 was inter-Kerbin/ light interplanetary ships, and 200 was for Jool Class ships.

These days, I spend a lot of time not really leaving the Kerbin system. I don't have the patience for the long missions anymore, as there's not much new to see.