Kozenger

I haven't tried double atomic and single jet yet, will have to give that a shot. I find it so satisfying when I can get an SSTO into LKO and have 3 or 4k deltaV. To me it feels a lot better than launching a rocket that only carries 10% of its mass into LKO.

Having three types of engines was going to be what I was trying next. It means a larger ship which is something I wished to avoid but like you said the thrust on the atomic alone just isn't enough, if you don't air hog, to do the trick. You make some excellent points for the T30s over aerospikes. An aerospike is enough TWR on smaller ships like mine to reach LKO. The main reason why I got into using aerospikes over T30s is the lower profile. Before I got my stick it was tough to have a strong angle of attack and not clip the engine on take off. The only issue of having the lower thrust to weight, aside from trying to get to speed to hit orbit, is longer burn times. Once you are in orbit the extra thrust to weight doesn't have as much value, as long as you have above 1 to escape from where ever you are going you can plan for longer burn times. Thank you for the information.

You seem to be assuming a lot and not really understanding what the original question was. I have no problem in the "jet phase". I am not trying to use the atomic engine to get off the runway. The specific impulse of the atomic engine at 24km is almost exactly the same as it is at 100km. I do not and would not use the atomic engine until the jet engines were so starved for oxygen that they ceased to function. My problem is specifically not having the thrust necessary with the atomic engine, unless I air hog, to maintain the speed necessary after the jet engines cease to function to reach LKO at my space plane size.

I gave some numbers in my first post regarding what I feel is air hogging and how fast/high on average I get off the jet engines.

I agree. It largely isn't the best way to go about things when you consider the diversity of planets in which to visit. No single craft is. You could follow the same logical reasoning with rockets and landers. What works for Duna or Laythe probably doesn't work well for Eve. And exactly what you mentioned about the wings. Once you get to LKO the lack of atmosphere in the vast majority of places to go will make your wings more than useless. Its actually a determent to the craft because it is weight that isn't serving any purpose for the craft at that point. To answer the question as to why bother. Because I think it's fun. It's the same reason why I mentioned that air hogging was not an option for me from the start. I can do exactly what I want to do if I air hog but I choose not to. Trying to overcome the artificial limitations that I place upon myself is a fun challenge for me. To me it's like having unlimited resources and and being asked to build a car that can fly, float on water, and do a quarter mile in 15 seconds. That's an interesting challenge. Do we have cars that can do a better quarter mile ? Do we have boats that will function better in water ? Do we have air planes that can fly better ? Absolutely, but because I have those unlimited resources at my disposal it becomes something more academic. Becomes a what if I could... ?

Well, that's exactly why I wanted to work in the atomic engine. I wanted longer range than Kerbin influence without refueling. Without the atomic engine a SSTO of that size won't get far without infrastructure already in place to refuel the ship every time it does a transfer.

Thank you for your information. It's appreciated.

My question is if it's practical to try and get an SSTO, around 15 to 20 tons, out of atmo with an atomic without air hogging. I've been having problems trying to create a SSTO that uses atomic engines without air hogging or stacking. I tend to build in the 15 to 20 ton range and most of the space planes I get in atmo with the aerospike tend to have ~200 to 500m/s delta v to spare. Which is ok as long as I dock before I leave a planet to refuel but it's always tight and isn't enough for a few places. Most of my attempts to use atomic engines have had issues maintaining speed while trying to push out of atmo. In general I will be flying at around 1200 to 1600m/s and at 22k to 24k altitude but even in my smaller craft the atomic just doesn't have the umph to get me up and out before I lose too much speed. Again this is an issue with my personal limitation of not wanting to place more then 1-2 intakes per jet engine preventing me from getting out of atmo with an atomic engine. I can air hog and get into a LKO with 3000+ m/s of delta v but I don't find that a fun way to play. Any suggestions would be appreciated as I've ran into a creative wall. Thanks for your time and input.