QF9E

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  1. I got back from the MUN! And with all science that a Caveman can gather from Munar orbit! Well... I forgot a crew report high above the Mun, but I can do that one during the next Mun mission. It took a few attempts to get my Mun rocket design from the previous post into orbit. Sending it to the Mun turned out to be easy: start burning prograde once you see the Mun above the horizon in LKO and you will get a retrograde encounter with the Mun. I then had to wait until I entered Munar SOI before I was able to do a course correction to get onto a polar Munar trajectory, and after that I entered low Munar orbit. There I gathered all orbital science; this took a while because I wanted to gather EVA reports for all of the Mun's biomes. It turned out I did not have enough fuel to get back to Kerbin: whatever I tried I could not get the Kerbin periapse below 160 km. I therefore launched a rescue mission, which gently pushed my craft until its periapse was inside Kerbin's atmosphere. I then proceeded to land both craft. Full report: https://imgur.com/a/1hHxkGr. Some highlights: Liftoff! My victim passenger has the worst best seat in the house! Bob riding his rocket inside the Mun's SOI Munar escape trajectory. I did not have quite enough delta-v to get my periapse inside Kerbin's atmosphere. I even used my craft's decoupler to give an extra push, but it was not enough. Jeb giving Bob a gentle push to get his periapse inside Kerbin's atmosphere. My science haul. I completed all "in space" science around the Mun, except the crew report high above the Mun.
  2. I finally finished a rocket capable of taking Bob to low Munar orbit. It hasn't been easy to build a rocket within the 18 ton limit that Can take all tier 1 science equipment to the Mun (note that this must include a crew capsule, in order to be able to do crew reports) Can do this with Bob not inside a capsule. Bob on the outside generates a lot of drag, even when he would in real life be shielded by stuff above him. Avoids vapourizing Bob on the way up. I've found that I have to fly a much more lofted - and hence less efficient - trajectory than I normally would to avoid overheating poor Bob Avoids accidental ladder drives. I had a really strange one where, with Bob on a ladder, its PE and AP would continuously vary. I eventually found that this was due to Bob clipping into a Goo canister underneath the ladder. I did not have enough clearance between the ladder and the Goo canister, apparently. I would not dream of cheating by way of ladder drive, but avoiding accidental ones was a new one for me. And when I had a design that worked, I forgot to include an antenna, which means that without crew onboard it was not controllable at Munar distances. I am not used at all to tier 1 facilities: in my mind the Mun is close enough to Kerbin to not need extra antennas. That said, here's the design. Note that I no longer use the structural tube to house Bob: I found that a decoupler at a strategic point pervents Bob from flying out of his cubbyhole during launch. This saved a component, and more crucially, made the rocket a bit less tall, so that it (just!) clears the 20 meter limit without needing 2.5 meter parts. I found a single Reliant engine on the 1st stage combined with 2 sparks on the second stage, in pods so that they can fire in conjunction with the Reliant, to be an excellent combination that gives ample thrust at lift-off (TWR = 1.35), is relatively light and has good TWR on the second stage without adding undue mass or drag.
  3. On that point we agree. Cessnas and airliners *can* do high bank turns (don't discount the maneuverability of an empty airliner with just enough fuel onboard to complete a demo display) but it should not be necessary in normal operation. In my space shuttle I'll do high bank turns mostly to shed excess speed. I have been doing 90 degree banked turns and even split-S, but that is because my energy management is something that I need to work on. As you say, if everything goes right you don't need that kind of maneuvers.
  4. I am going to disagree with you on that one. Whenever you roll the plane, regardless of the amount, the vertical component of the lift vector will be less than when flying straight. This is even true for real-life gliders. It is not very pronounced, and certainly not in KSP with its simplified flight model, but I've also experienced it in KSP. In KSP I use pitch trim to keep the nose up.
  5. Your point cannot be stressed enough. Airplanes DO NOT TURN by giving yaw input (well, technically they can do a flat turn but it will look really awkward). Airplanes turn by banking them, which means the lift vector points to the side a bit. This sideways force pulls the plane into a turn. It also means that the lift vector isn't pointing upwards as far, so if you don't correct for it the nose will drop in a turn. The correct way to execute a turn is to bank, then pitch up slightly. If it is a sustained turn, then use pitch trim to keep the plane in that orientation. The fact that KSP by default enables all control axes for all control surfaces does not help either. You really should disable roll on the vertical stabilizer or else your plane will do a combined roll / yaw every time you want to do a roll. I hardly ever give yaw input in KSP, unless I want to do a side slip. Edited to add a little story that I find quite amusing: I have had a few real-world glider flying lessons, and my instructor was surprised and a bit annoyed that I knew all this going in. My nerdy attitude at the time would not have helped with his annoyance either: He asked me when telling about the plane on the ground what happens when you pull back on the stick. I answered "the elevator will turn upward". "And what happens next?" "Nothing. This plane is stationary on the ground at the moment." In hindsight he probably was looking for the answer "the nose will pull up". Same will roll input: "What happens when you apply roll input?" "The plane will yaw in the opposite direction." Which is true, especially gliders suffer quite badly from adverse yaw due to their aerodynamics. But not what he wanted to hear ("The plane rolls in the direction that you move the stick"). Should not be surprising that I quit after just a few lessons.
  6. Good advice. Almost no-one will be accustomed to m/s. Mach 1 is "only" 340 m/s or thereabouts, so speed can be deceiving.
  7. @Fraktal posted this in the old thread: Welcome to this new thread! From what I read here you are quite an experienced flight-simmer, and I understand your frustration. From what you describe I think you play with SAS on, as you describe some of the very behaviours that I outlined in my previous post. KSP, especially if you play with mouse and keyboard as I do makes it almost impossible to fly a plane like you would do in other flightsims (or when flying for real, for that matter), by giving small control inputs. If your approach speed is 150 m/s while your take-off speed is 80 m/s your approach speed is way too high, and a flare at that kind of speed will result in overshooting the runway, simply because the plane will keep on flying. And if your flare results in a stall 30 meters above the runway you started the flare too early. I'm sorry if this sounds blunt, but that would be no different in a real airplane. Perhaps you don't give yourself enough room to get your airspeed right? Have you tried doing an extra long final approach where you focus on getting the glideslope and approach speed correct? Problem with KSP is of course that you have no real way of knowing what the correct approach airspeed is for your aircraft design, and what glideslope you need to maintain that speed, so you'll have to do some testing. With SAS off it is possible to side slip in KSP, by giving opposite rudder and stick inputs, and it will slow down your plane. If I have the time I will make a video with an example. Thanks for the link! I use pitch trim to fine-tune my ascent with a spaceplane, and leave SAS off. With SAS on it feels like I am fighting the SAS system instead of flying the craft.
  8. This started as a feature request for a longer runway, but evolved into a discussion on how to take off and land airplanes in KSP. To prevent us hijacking that thread, I made the current one. In order for this to become a bit more general, it seems that many KSP players have trouble taking off or landing airplanes on the KSC runway, to the point that they believe that the 2.5 km stock runway is not long enough. I haven't had this experience: my 40 ton Shuttle is able to land on the KSC runway (and, in a pinch, the Island Airfield) just fine, even loaded with 80 tons of cargo, or with an asteroid on its back. And my hope would be that players with lots of experience with airplanes in KSP - perhaps including me - can answer questions of less experienced players and help them on their way to become better aircraft designers and pilots. Ok, that being said, how to go about designing, testing and flying your own airplane designs in KSP? I believe this is one of the hardest things to do in the game. The reason is that your job is a combination of two things that are both seen as very difficult in the real world: aircraft design and test piloting of high performance aircraft. Here's a few tips that I gave in the previous thread: One tip that I want to repeat because I think it is a very important one and it is in danger of disappearing in the mass of text is this one: If at all possible, fly your plane with SAS OFF. SAS will try to keep the nose of the airplane pointed in a fixed direction in space. This has a couple of unwanted consequences: * It is virtually impossible to make fine course corrections, as you are in effect fighting the SAS system * It makes it impossible for the plane to find its own balance, often forcing the plane into a slip (which means that it flies with the nose of the plane pointing to the right or left instead of straight ahead, adding extra drag) * On long overland flights, it forces your plane to climb ever faster, which is due to the curvature of Kerbin. SAS keeps the nose of the plane in a direction which is fixed in space. * It appears that SAS is momentarily switched off when you are giving control inputs. This has the rather nasty consequence of nullifying pitch trim when you give small roll or yaw inputs as course corrections, often dropping the nose of the airplane. If this happens on final approach, you are in real danger of crashing your plane. Seriously, SAS is a lousy autopilot. I only use it for long overland flights. But enough from me for now: I'd love to hear your tips and tricks, as well as your questions and any problems that you might have in flying or landing your airplanes. And maybe someone is able to answer a question of mine:
  9. In my Shuttle challenge series I repeatedly landed a 40 ton Shuttle on the runway, at various times with 80 tons of cargo or an asteroid on top, and I have never needed more than a fraction of the runway length. I also landed my Shuttle's flyback booster on the runway numerous times, and despite it being considerably bigger than the Shuttle, it also never needed the entire length of the runway. Hell, I have landed both shuttle and booster on the Island runway a few times after I overshot the KSC. But there is one thing I would like to see: a full length taxiway alongside the runway, with a couple of additional runway exits. Especially for a Shuttle with flyback booster, it would be nice to be able to vacate the runway at various points along its length after landing the first one, to make room for the second landing. For people who have a hard time taking off from or landing on the runway: Add enough wings to your craft that it is able to fly at a reasonable speed, no more than about 100 m/s. For comparison: touchdown speeds of real-life high performance aircraft vary from about 70 m/s (F-16) to 100 m/s (Space Shuttle), 105 m/s (X-15) with 123 m/s (F-104 with its blown flaps inoperable; with these flaps touchdown speed was 85 m/s) the maximum I have been able to find. Don't have the nose of the craft pointed down too much when it is on the runway. That way it will be hard to lift the nose (a maneuver called "rotate" in aviation) and get the wings to generate lift. If the wings point downwards with respect to the airflow, you are generating downforce. Useful if you are building a Formula 1 car, not so much for a plane. Put the main landing gear slightly behind the center of gravity. If the landing gear is too far back you will not be able to rotate. I see a lot of spaceplanes that are only able to take off by running off the end of the runway, and often the problem is that the landing gear is too far back. A good test is to do a high speed taxi on the runway, and see if you are able to rotate. If your craft is well-balanced you should be able to taxi your plane a considerable distance on the main gear alone at a speed just below touchdown speed. A high speed taxi run also enables you to test the brakes. Try to land with as little speed as possible while still flying. Approach the runway somewhat above this speed, and once you reach the runway threshold (at about 20 meters altitude or so), pull up slightly to lose more speed - this is called a flare. If done correctly you will start losing speed without gaining altitude. If you do gain altitude when flaring, try again with a lower approach speed. A more general tip is to try to design aircraft that are able to fly with SAS turned off. With SAS turned on, a KSP plane does not fly like a real plane at all, as the SAS will try its best to keep the nose of the craft pointed in the same direction, whatever you do. Learn to use pitch trim (Alt-S for trim up, Alt-W for trim down). Pitch trim is used in real aircraft to keep flying level without applying any force on the flight controls. The higher the speed of your craft, the less pitch trim you will need. And another general tip: consider playing a different flight sim to learn to sim-fly. I for one can't wait for MS flight simulator 2020. Building and flying planes in KSP is in some respects much harder than, say, sim-flying a Cessna in MSFS: in KSP you take on the roles of aircraft designer and high performance test pilot, two jobs considered very hard in the real world. Whereas the flight characteristics of a Cessna are very well known, the performance of any KSP airplane design is anyone's guess untill you start flying it.
  10. Some progress: I have reached LKO and gathered all In Space {Low | High} science from Kerbin. I have also designed a rocket that is capable of reaching the Mun, although that one has not yet been successful: I have reached the Mun's SOI, but was unable to harvest any science as my craft had run out of electricity... Next time don't forget to switch on hibernation on my probe core. Space is hard, especially for Cavemen. My LKO craft. Piloted by Jeb, with Bob in the second capsule. Before launch, Bob performs an EVA and relocates to a ladder inside the structural tube directly below his capsule. Note the gap: I haven't found a way to keep Bob safe without leaving a gap. The gap itself is made simply by first connecting the structural tube to the capsule and then moving it down. Bob doing the science dance in LKO. My current science archive. I have gathered all possible science from Kerbin. Next up: the Mun and Minmus My Munar rocket. I have substituted Jeb with a probe core, which lightens the craft considerably, for a significant increase in delta-v (and a much harder ascent, as the best probe core available to Cavemen lacks a prograde hold autopilot - I learned that I am not very good at flying rockets manually). I have ascertained that this craft is capable of reaching the Mun's SOI, but I haven't done any science with it yet.
  11. I like it a lot! Much more evocative than the old Mun badges. Also an interesting contrast between the featureless Mun in the foreground, while Kerbin has details in the background. It reminds me of the business-like description of the Moon by the Apollo 8 crew in contrast with their delight at seeing Earthrise with their own eyes.
  12. I have since completed all remaining surface experiments (mainly the Splashed science in the Southern Ice Shelf biome), as well as collected all Flying High science. This has netted me about 115 additional science. In itself this is not very noteworthy, but it implies that completing a Moderate difficulty Caveman challenge should be possible without entering space. My current science status. I cannot unlock any further nodes in the tech tree under Caveman rules, but I can still gather more science points. This excess of 164 science points would be enough to unlock all tier 1 science in a Moderate difficulty setting.
  13. Thank you! One minor point: could you please correct my name in the hall of fame by replacing the 6 with a 9?
  14. Thanks! Although I'm sure I've seen a non-space Caveman before, I just cannot find it anymore... Mine started as an attempt to visit every biome on Kerbin and collect all the science. On the way I realized that it would be possible to finish a Caveman playthrough with just the surface science, if it would be possible to get the splashed science for all biomes as well as the landed science on the water. I found some old threads on this forum with possible "splashed" locations, and some of them turned out to still be valid for KSP 1.8.1.