Surefoot

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Everything posted by Surefoot

  1. @Taverius: why not the batteries ? We have a whole set of stock inline batteries for all diameters, but just not shaped for B9 SSTO fuselages. That means using unwieldy adapters and so on.. oh well. As for the docking port, i see your point for S2, it's big enough so it doesnt compromise too much the aerodynamics, but on MK2 it's protruding quite a bit. For the attach nodes on quad 1.25 S2 wide adapter i had the problem of outer objects overlapping whatever i wanted to put in the center node, usually using a 2.5m adapter. I know you can put a tail there without any problem but other stuff is overlapping the outer 1.25m attached objects. @Dragon01: yeah but it disrupt the whole looks, see what i mean Another idea for the cargo bay: a new part which would be a docking port mounted on a rotating arm. Could be a fuselage section. This would save a lot of hassle trying to get stuff in and out.
  2. Some comments as i have been using B9 extensively for my SSTO's. We are missing some in line fuselage section options such as - inline RTG (or retractable inline solar array) - so far i have been using the ion pack generators but these are round shaped only. - inline docking port section for MK2 and S2 - batteries shaped for the above mentioned fuselages - Maybe a downwards facing cargo bay. Sending rovers to atmosphere planets with FAR is quite a challenge without that (egg shaped capsule with proc fairings can do it, but it's not as pretty as a nice cargo SSTO delivering the rover directly to the surface..) Also the S2 Wide multi mount adapters have overlapping nodes, especially the 4x1.25m engine mount, everything overlaps which makes mounting anything there with symmetry quite difficult.
  3. @Taverius: hey thanks mate ! Looking forward to that new B9 version. What i missed there apart from a dock port equipped fuselage section and procedural control surfaces, was maybe a bit smaller stabilators. Here i used the smaller B9 stabilator, but i think it's still a bit too big for that plane (fine for the S2W variant though), and my only alternative is the R8 which is too small. And too bad for fuel loaded wings @Raven: with the v0.21 SAS you could fly an unstable design (not TOO unstable though). v0.22 seems to be over-compensating, instead of using the derivative of the target value it uses it directly, thus applying corrections even to micro changes (such as very small roll axis changes on my plane above), CREATING unstability instead of reducing it ! Only solution until v0.23 is to deactivate SAS especially for landing and use a stick.
  4. Success. Here are the pictures of my latest prototype flight test: Changes from my previous design are: * Added another small LFO tank section at the front following Ferram's recommendations (also had to give some extra deltaV, previous design was VERY tight for a Laythe target and had no margin of error). Results in more pitch stability, but seems to increase mach tuck effect at transonic speeds. Still can keep control so not a biggie. * Added front canards to increase pitch stability (as per Ferram's suggestion, and to mitigate mach tuck effects) * Added more length to the delta front section of the wings, to increase wing surface area (used a 3rd procedural wing clipped in between) * negative dihedral on the whole wing area (one small rotation step in the SPH, not sure about the exact angle). The net result is very good stability in most flight situations. * Move the tail fins a bit apart and gave them a slight tilt outwards, seems it's working (thanks again Ferram !) * Increased the span of the rear part of the main wing, to account for the increased weight and length (added tank). Increased sweep a bit too. It handles as beautifully as the looks suggest. Roll is very sensitive (like a jet fighter basically), new v0.22 SAS is totally lost there. Deactivate SAS and the plane flies very nicely. Landed without SAS at north pole, almost lost control just before landing (i use keyboard !!), AoA at low speed must be kept tight to avoid a stall (i guess due to the highly swept wings). It also wants to dutch roll like crazy so yaw inputs have to be very subtle and progressive.. I can now throw it into a stall while supersonic, by giving it too much pitch input, i guess it's a compromise i have to live with (like the real world counter parts, so it's not surprising). Good thing is in most cases it seems to come back to stable / prograde by itself and not go into a spin. The 3 tank sections allow for more precise fuel balancing (wish i had fuel loaded wings..). Flight data with unstable SAS roll (but stable normal flight): Jeb approves this spaceplane and FAR ! Now we are still missing fully retractable ladders and gear bays. And maybe a MK2 docking port section (there is a 1.25m stock part already that does this) as the B9 shielded port is still protruding quite a bit. Quick questions: do you think that reaction wheels make any difference in flight ? I got 2 of them (one in front just behind the cockpit, one in back just before the engine twin mount) for space, wondering what are their effects at subsonic and supersonic speeds in atmosphere. Also how do oblique surfaces affect flight, i am thinking not only dihedral wings but fuselage mounted winglets ? Also do you think it's worth giving the same angle to my control surfaces (front and back) ? @Raven Coldheart: i almost did a cobra with this design (which now that i think of it, is not unlike the SU-27 viewed from top), went to about 60° AoA and back. I guess the front canards helped there. It was not controlled though it was a stall.. (too sudden pitch) for control you would need proper thrust vectoring.
  5. I love this mod for the inline generators. The engines though are too heavy (if we add up everything, power generation and xenon tanks included) to give any significant deltaV advantage over nukes or even some good ISP rocket engines. Or did someone manage to make a really useful design out of them ?
  6. The speed tape is still going downwards on your photo there
  7. Thanks a lot. The first screenshot shows my revised design: the wing sweep is higher, and the tails are tilted outwards (does that increase separation at all, the root is still around the same spot). Pitch instability is an interesting way i did not explore fully yet: maybe adding canards like on my earlier design (the one with the close vertical tails) would solve the issue ? Sideslip i noticed on my first tests, adding the winglets removed a lot of it, mach 3+ flight data show a sideslip angle of around -0.1° (used to have around 2° of sideslip angle without them). My designs are fully strutted especially the mid-rear part that is under a lot of stress during pitch manoeuvers. One thing i noticed is the very high wing sweep make for a fantastic supersonic stability. I can do manoeuvers at full pitch without going into a stall, it keeps the AoA tight at all times, but subsonic flight is a nightmare the plane wants to go everywhere but straight (and the 0.22 SAS is completely lost there, makes the situation even worse). I have no issue with the fuel transfer, it's totally part of the experience of flying a supersonic (and i am aiming for an optimal design, minimal weight and parts) - also the rear positioned airbrakes improve aerobraking stability (got 6 of them, 3 top side 3 under the fuselage). OK going back to test flights - procedural wings + FAR = infinite possibilities !
  8. Hi Ferram, first i have to say thank you for your awesome work. It has totally redefined what KSP is for me, and now it brought me over the 170 hours mark. Latest craze for me was to build a Laythe SSTO, with a docking port for refuel. I am using B9 and procedural wings there. Recounting my experiences with it: In 0.21 i found out that a design (very) loosely based on F-18 with a bit more swept wings and wingtip "winglets" was working very well. Quite stable (ignoring the natural dutch roll tendency if i try to yaw excessively), good AoA, a bit twitchy but handled like the above mentioned jet fighter. Using twin Sabre's as propulsion. 0.22 comes with the new SAS, and here my problems start: this kind of design is a bit unstable by definition, in 0.21 SAS had no problem handling the very slight movements necessary to make it fly straight. In 0.22 the SAS seems to overshoot by quite a bit.. shaking and wobbling nonstop, sometimes even totally losing control (went into a spiral spin at mach 5 with a prototype: nasty). What i found out is my designs had a huge roll unstability. This is the roll-unstable design: I got an almost similar design on which i added negative dihedral on wings (like on jet fighters) which solved the roll unstability. Wondering why i did a quick search which produced this: http://www.b2streamlines.com/EffectiveDihedral.pdf Tried to add some 45° stabilizers (very small winglets under the fuselage) with no success. Maybe the positioning was not good (tried a forward position, behind the cockpit). Here on this screenshot you can see the negative dihedral (got vertical tails on this design, not sure it helps compared to the tilted tails of my other design): I still got unstable flight at low speeds, but in supersonic mode i can throw the plane around mostly safely (did a huge bank turn at mach 3.2, went perfectly well with not even a minor stall, and this with 100% pitch input). The low speed unstability is a problem for landings, though, so i have to find a solution there. Variable geometry wings are out (no mod to allow that properly, yet). Thinking of going to diamond-shaped wings with elevons, not sure about mach tuck though without independant mobile surfaces ? There, my thoughts so far, here are pics of my first trip to Jool with the vertical tail fin design: Refuel stop in LKO before the big jump to Jool Aerobraking. Had to transfer fuel to the front tank for stability I'll post more designs and thoughts if you want. I am having a blast with that mod. I just need more procedural parts
  9. Most urgent would be procedural control surfaces and winglets. The R8 can only go so far.. avoiding mach tuck in FAR means having bigger control surfaces, and at the moment the choice is limited even with mods.
  10. Hi hi, neat plugin. I tried something in the SPH though and got a weird result: i assembled a few B9 fuselage pieces together (basically in line MK2 parts) and once welded, each original part is rotated 90° up, maybe like they were saved in the VAB or something. But the global layout is still the same the parts are in line horizontally ! So, the end result is quite messed up. I'll try and post a screen if you dont see what i am trying to describe.