AeroGav

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About AeroGav

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  1. Stock , non-folding rovers seem pretty useless. The widest one that will still fit the largest cargo bay (mk3) still has a track width that's so narrow it will be prone to tipping over/flipping. Try to build with a lower Cg, then you have body parts hitting the ground because it rides so low. The mk3 cargo plane i built to carry it, with the largest size landing legs, had much longer wheelbase, much wider track, better ground clearance, and stronger wheels. It could drive safer at higher speeds over the surface than the rover could, and used minimal fuel to do so.
  2. It was my attempt at an F35 joke..
  3. @astroheiko My Career mode has stalled while i work on the Shuttle challenges, my plane was developed in Sandbox. Well, my plane might not provide much comfort, but bear in mind it is the lightest of the three things to reach Tellumo orbit, 100% stock, and also the "most re-usable". The other two space planes throw away more than half the vehicle on the way up. Mine "only" drops two Rapiers and two Whiplashes. I was trying to minimise the amount of dropped parts, rather than maximise size of crew accommodations. I used Alt F12 menu , Cheats, Set Orbit to put it in orbit of Tellumo for the test flights. Then I re-enter with "ignore max temperature" cheat. If I empty the fuel tanks, it can re-enter Tellumo safely, however the Rapier and Whiplash engines are destroyed by heat. This is because they are very exposed out on the wing tips. I could redesign to put them around the main fuselage , so they will be inside the "bow wave" created by the vehicle's nose on re-entry. As I said before, for the test flights i used cheat menu to get the plane in position. Even then, it was still a very time-consuming process. However, it can take off to orbit from Kerbin or Gael without dropping any engines. If refuelled in orbit, the delta V is huge (lots of liquid fuel storage, nerv engines). For role play reasons , i'd want to use a Claw to attach a crew cabin or something to the side of the plane while it does it's Hohmann transfer - i don't expect a Kerbal to sit in a chair for 3 years ! On the surface of Tellumo, you'd need a Claw-equipped, ISRU rover to refuel the plane, since it cannot re-enter fully loaded (too much heat generated at the higher mass). So , that's a few extra components, but it's the best Kerbin - Tellumo shuttle system i can come up with. You only loose 2 rapiers and 2 whiplash per round trip. You also loose the IRSU rover, which can never be transported back to Kerbin, but that cost can be spread out over a large number of filghts in a colonisation scenario.
  4. First we had the Saturn V, which was scrapped for the Space Shuttle which was going to provide "more affordable" access to space, except that overall it worked out more expensive. So now we're going back to the single use rocket model, but rather than simply build more Saturns they're developing SLS to leverage modern, highly automated manufacturing techniques and also use up leftover Shuttle hardware. In other words, it's going to be more affordable than the Saturn V which was cheaper than the Space Shuttle, awesome ! What's the bet that when you take the development and running costs of the entire SLS program and divide by the number of launches it eventually does, it manages to be even more expensive than the space shuttle? ............ I feel bad for saying it because at least they're trying to build something, and reality has fallen so far short of expectation since the 1950s you can rip any space program apart. Still , maybe the US airforce should commision whatever replaces SLS? One vehicle to handle military, commercial and space exploration. It will be stealthy, able to launch everything from cubesats to mars missions and really really affordable honest /trollface
  5. Mark 2 Fuselage parts are a "newbie trap" for would-be SSTOs. Almost every problem SSTO you see on the questions subforum relates to a mk2 design, and I too struggled with mk2s that could barely do more than orbit, until I tried my first mk1 and mk3 designs. These parts have 2 or 3 times the drag of mk1, but hold no more fuel. Yet, given the information available in-game, it is understandable why almost everyone attempting to build their first SSTO ends up using the parts hardest to SSTO successfully with. they look sleeker than mk1 or mk3. They strongly resemble the fastest jet built, the SR71 blackbird, with the Chines. much higher temperature tolerance than mk1, without the apparent bulkiness of mk3. mention of the "extra lift" in the description, makes those blended wing / body chines look like a great deal. In practice they produce about as much lift as the smallest modular wing segment, for over 100x the drag... For first time spaceplaners - just build a mk1 and use an inline cockpit , with the crewed bits mounted as far back as possible to keep them away from the heat. Mk2s can be made, but require advanced construction techniques like built in wing incidence to reduce fuselage drag (even with that, they still perform worse than mk1s without wing incidence) . On mk2s, the extra drag means there is a very narrow window between not enough engine (can't break mach 1) and too much engine (too much dry mass to have the delta v to reach orbit)
  6. A nuclear turbojet would also do the job. Please Squad, please. The most lightweight mod with one of those was called Atomic age, if I recall correctly. Or you could install Interstellar, but that is an 800lb gorilla of a mod.
  7. Enough for a landing on Minmus actually. Coming back you can aerobrake with multiple passes. Or just put a fuelling base on the surface.
  8. What about weight? How much does the weight of the panther compare with its real life counterpart? Also i doubt the ram air thrust gain is realistic of any jet engine yet made. 3.5 times the static thrust at mach 2.5? Don't think even the J-58 did that. Most jet engines loose thrust every knot you go above mach 0. They gain a bit of efficiency with alittude (colder air) but that's it.
  9. Mine did it too, though it needs a lot of refinement. I need to change the part attach order because it rolls constantly left at lower altitudes. Getting to the surface (don't have any mods that can put me there) to make each test flight, and the fact that it takes 40 minutes to get to orbit, mean i have not bothered.
  10. I'm pretty sure that if you set authority limit in SPH , when you "Deploy" that is the angle you get. However, changing authority in flight affects only the max deflection when acting as control surface, when Deployed they remember this function set in SPH? Funnily enough, I started work on a cruder version of what you describe more or less in parallel. I often design my spaceplanes with built in wing incidence, intended to be flown with near-zero body aoa. Note that when you set prograde hold on the SAS, it does not in fact give exactly zero aoa, but it applies a correction factor. For example, if you craft flies hands off at -5 AoA with no control input, SAS will apply uptrim and reduce the error to only -1. If it's set up to fly hands off at +5AoA, you'll get +1 on Prograde hold. It's a feed back correction system that's imperfect and can only reduce , not eliminate the error. Note that when you activate Prograde hold any pitch trim inputs you've made are ignored. Which brings me back to my point. By having a surface I can deploy, i can change the "hands off" natural AoA of the craft, and therefore the one that it settles at when Prograde hold is set. So, towards the end of the subsonic climb, we're nearing the transonic high drag zone. I "deploy" the surface, and my airplane now settles into an AoA that's a couple of degrees higher. This makes it climb more and delays the onset of the sound barrier. When it arcs over the top from this climb and starts approaching transonic, i toggle the deploy off again, and it settles to a lower AoA, and shallow dives through the sound barrier. I can also use this to damp out phugoid oscillations while keeping prograde hold on. Plane starts overheating during hypersonic climb? Deploy, to get more nose up attitude and climb faster. For re-entry, i'll leave them deployed to re-enter at a slightly higher aoa (coming in prograde gets rather hot)
  11. What is the delta V like once you refuel it? I accidentally came up with something organic looking, but yours looks a little more evolved. Mine's more of a Pterodactyl Can you put your mk3 bird up for download? I really want it ! Ps. I also had a career mode mk2 with an upside down cargo bay for deploying ground relays. It rode really low down on account of using large numbers of the small landing gear. When i used the action group to deploy the cargo, it used to squirm on the ground as the doors opened, looked like it was laying an egg.
  12. Best possible lift:drag ratio in the 1.4 mach up to orbital velocity (supersonic) range is about 4 to 1. There is little change between mach 1.4 and mach 6, so you might as well go fast and high, because at mach 5 orbital freefall is supporting more than half your weight. At a constant lift:drag ratio, that means lower drag which means less thrust needed to keep flying. In other words, if you're doing mach 5+, you'll be able to fly really high despite keeping AoA low, which makes for low drag and fuel consumption. If you're in a panther powered low tech ssto, you cannot go fast enough to benefit from this effect - these engines go from hero to zero between mach 2.5 and 3. So , you might be better off switching to dry mode, which doubles your ISP, and you should still be able to hold > mach 1.3. Failing that, of if the fuel situation is really desperate, go subsonic, as slow as you can bear. There is a really high drag region between mach 1.3 and mach 0.86, but once below that , the slower you go, the better your L/D. Obviously, you still need to avoid high AoA, so you have to get low when you get slow. In practice, this means not using the engines and just gliding down till just above ground level. After that, trim the nose up for 2 degrees of AoA and add just enough throttle to maintain speed. Not fun though.
  13. The problem is that being close to CoM, they won't be very effective at stabilizing yaw. The further aft of CoM the better, but on the other hand you don't want the tail to strike the ground when you pitch up!I often use twin tailbooms coming off the wing, but the OP wants a good looking aircraft above all else (it certainly is) so i don't want to go suggesting things which drastically change the appearance. I actually like the look of those radial intakes. They are useless, but honestly the drag is negligible compared with the vast barn door drag he's going to be getting off the mk2 fuselage parts, so personally I'd just leave them on because they look nice and logically this plane should have some intakes (pre-coolers really "shouldn't" work on their own). I do think the OP is really setting himself a mission impossible though, wanting an interplanetary mk2. If he can make it work, I'll be very , very impressed. The drag off those mk2 fuselages is huge. You can ameliorate that by adding incidence to the wings but if you're after aesthetics and have the OP's eye for detail, that's not an option - there is a nice flat chine running the whole length of the fuselage that's meant to blend smoothly into the wing all along it's chord. If he adds incidence, the leading edge will stick up above it and not connect with the fuselage at all while the trailing edge droops below. That drag means he needs 3 jet engines, weighing 5.2 tons, to get hypersonic. He needs a ton of oxidizer to get to orbital velocity. The mk1 in the spoiler above, has a 37 ton TOW and can get hypersonic on one rapier thanks to low drag. It has so much lift and so little drag, it can continue to climb and accelerate with 2 nervs only (the rapier never uses closed cycle mode). After reaching 150km circular orbit, it still has 3700dV left, and a 0.35 TWR on the two nukes. To cap it all, the pointy cockpit looks amazing but due to overheating will not allow the most efficient flight profiles, getting to 1600m/s on air breathers. Interplanetary designs tend to have lower TWR, but with a pointy cockpit you need a high TWR and not stay around in the upper atmosphere.Here's a mod of a craft someone else posted on the forum, I managed to get 3700+dV out of it in LKO, but it has angled wings to lower drag. The mk1 fuselage tanks running either side of the body help to hide the messy wing/body join that results. Without angled wings, it'd probably need more engines to hit mach 1, and i'd need way more than 440 units of oxidizer to get to orbit (as it stands, a small kick to get us from 1400 to 1700 m/s is enough for the nukes to take us the rest of the way), For the first 9 months or so playing this game, I created mk2's with flat wings. The best i could manage was a design with 1 rapier and 2 whiplashes, 2 nukes. It would jettison the whiplashes once flamed out, and it had enough delta V in orbit to reach Minmus, where it could refuel off my surface base. Fully SSTO I don't think i could even manage that.
  14. Understood, on a drag per rapier fed basis the Shock cone is superior, but i don't really do designs with one shock cone on the nose feeding multiple rapiers at the back or on nacelles, i just don't like the look much. I normally go with inline cockpits and want something to put in front that keeps the cockpit far back from the heat. On a mk1, engine pre-coolers fit the bill nicely. I can't use a fuel tank because there is already usually more fuel ahead of CoM than behind it, due to the way engine mass tends towards the rear which makes the CoM aft of the halfway point on your fuselage. (pre-cooler ahead of cockpit here) For mk2 designs, i often put my nervs out on nacelles. I want the NERVs near CoM, but that means if i use a fuel tank as the root part for the nacelle i've got fuel mass ahead of CG again, with the resultant full/empty CoM shifting. Pre-cooler makes a nice convenient root. (pre cooler engine nacelles)
  15. I actually like precoolers, they are slightly lower drag than the shock cone and adjustable ramp intake. The shock cone can feed 2 rapiers of course, but it's not hard to find room for 2 coolers on a ship. They are also a part you can stick at the front ahead of the cockpit to keep it further back from re-entry heating, or to form an engine nacelle without adding too much fuel mass ahead of cg. Just put nose cones on the front ! I'd probably go further and put the RCS ports themselves inside the cargo bay. Below 70km, you do not need to translate up/down/left or right. You can point the nose with aerodynamic controls, thrust vectoring, and reaction wheels. Once out of the atmosphere feel free to open the cargo bay, this will allow the RCS to work and you can translate up/down for docking. Swap that pointy cockpit for an inline. During re-entry, it's going to be very prone to overheating. During launch, if you're flying an efficient profile and getting the most possible speed out of airbreathers, it might also overheat. Finally, two swivels might be too much rocket engine for a ship this size. It will work but won't break any payload to orbit or delta v records. One would be enough, but actually, as you have the Whiplash, you also have the Dart Aerospike. I'd pick a single Dart, it has a much better vacuum ISP. Put a reaction wheel in the cargo bay to make up for the lack of gimbal.