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Juno_Atlas_Saturn

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  1. If the plane is bouncing after it has stopped moving, it sounds like the gear is attached to something insufficiently rigid, such as wings. If a plane is sufficiently heavy, and has gear that is attached to wings or other parts, the otherwise motionless craft will often bounce as the wings are actually flexing under all the weight. Even if that didn’t happen on the ground on Kerbin, the wings might’ve been close to that point and are failing in the higher gravity of Eve. Try adding struts to make them more rigid- that should fix it. Alternatively you can move the gear to the fuselage but that might come at the cost of stability during landing.
  2. A major use for the aspirational maneuvering is that we can use a vehicle we place in orbit to figure out timing and delta v requirements from LKO for various destinations and thus inform future mission design. The Delta V Map goes part of the way towards resolving this but it would be really neat to have tools that allow us to plan theoretical trajectories first and then build capable ships/time maneuvers after. In essence, a mission planner.
  3. For those early career high-altitude survey contracts, I, like many of you, have traditionally opted for a combination jet engine/rocket engine plane, where the jet engine gets me to the contract location and I then jump to the necessary high altitude using the rocket. It gets the job done, but it's tough to meet early game weight and part count limits, the craft is often limited in range, cruising speed, and number of high-altitude jumps, and I'm eager to ditch the whole design as soon as I unlock new tech nodes (especially the Panther). What if I told you there was a different way to fulfill those contracts, where all you need is...drumroll...curtains parting...the Juno? Though Junos are generally low thrust, low altitude engines, they're actually pretty capable when you use a bunch of them on a lightweight aircraft to get a high TWR. Using only four, I managed to get a craft to 1.5-2 TWR depending on fuel level, which was enough to reach a 600+m/s cruising speed, 630+m/s max speed (see second image below of the plane descending from cruise in preparation for a jump), and a max altitude of over 20km per jump (see third image below). Because it can cruise at over 10km and 600m/s, it's actually got a pretty big range as well, and if I need to reach a faraway target I can load up the Mk1 fuel tank (see image below), and by the time it arrives at the jump point it will have used enough fuel to get the TWR back up to the level where it can support a high-altitude jump. Some notes on the design (see first image below): This design uses well under 30 parts (so you can customize with the science parts of your choice), meets all early game runway/hangar limits, and doesn't use anything beyond tech level four. I experimented with using a longer tail/traditional front wing/rear tail body design to minimize the risk of flipping, but any gains in stability were offset by a lower max speed and more limited turning ability that prevented me from going fully vertical in the jump, and ultimately limited the plane's max altitude too much. The engines are placed as far forward as I can without limiting a pilot's ability to exit the craft, and the rear wings are as far back as I felt comfortable with, which enabled me to nudge the COL behind the COM. The COM is even more forward when the Mk1 tank is completely full, but I rarely keep it full so I can maintain a high TWR. In general, having the COL really close to the COM provides maneuverability that helps in transitioning from supersonic horizontal flight to a vertical high-altitude climb, and in any event the plane doesn't really have a flipping problem. Control Surfaces - I limited all of the control surfaces (especially roll) below their defaults, because otherwise the plane can be a bit twitchy at high speeds. I also recommend using fine controls for most if not all of the flight. I experimented with increasing the AOA of the rear wings to squeeze out a little more efficiency while cruising, but the plane kept flipping on takeoff. Leaving the wings horizontal eliminated the issue, and the plane is surprisingly efficient as is. Flight Tips: Be gentle when pulling up to take-off! The plane isn't particularly flip-happy, but the only time it would happen is when I pulled back too hard during takeoff. This thing builds up speed really quickly, so you should be able to nudge it into the air with relative ease. To repeat what was stated in the design tips: consider using fine controls for most/all of the flight. Use the lower atmosphere to build up speed. I shoot for an AOA of no more than 10 degrees until I reach 5-6km in altitude, and then 5 degrees or lower until I've reached around 600m/s and between 8.5-10.5km cruising altitude. I can usually get a fuel usage rate of .08 units per second or lower (visible in the resource app) under those cruising conditions. Once you approach the target location, descend slightly to max out your speed (I usually get around 630m/s), and then gradually (I can't emphasize enough that it has to be gradual) raise the nose of your craft until you're fully vertical at around 18km- you should be able to hit 20km in altitude like this, which should be sufficient for most high-altitude Kerbin survey contracts. The turn needs to be gradual; you're looking to convert horizontal speed to vertical speed, not rapidly dump speed/raise drag with a sudden attitude change. Keep an eye on your speed and g force meters. If your speed is jumping down rather than slowly descending, or if you encounter any high g forces, you're probably wasting energy, and your max altitude will be lower. Unlike rocket plane jumpers, where you try to go vertical as quickly as possible to make the most efficient use of your limited oxidizer, don't go fully vertical too quickly. You can only raise your apoapsis if the Juno is thrusting, so until you reach 18km keep shy of full vertical so you can squeeze out a few more seconds of thrust while climbing, or at least until your apoapsis display shows that you've exceeded your target height for the jump. Once your engines flame out, go full vertical to maximize the use your remaining airspeed which should nudge that apoapsis a teeny bit higher before it starts coming down due to drag. Landing: This plane handles just fine at 50m/s or below. When coming in for a landing I often have the throttle at about the 1/6 mark, which gives me just enough speed to get into position without needing to land at high speed. As an early-game craft, there are no airbrakes/reverse thrust capabilities, so you'll have to bleed off speed by maneuvering alone (from 600m/s to just over 100m/s) when approaching the KSC and then using the rear landing gear brakes only (there's no brakes for the front wheel). I haven't needed to deploy ailerons to improve low-speed handling but that's always an option. As you unlock more tech nodes/higher KSC levels, you can add more Junos, streamline the landing gear/wings, or make other improvements, but even without those this is a really capable plane that you can continue to use into the mid-game for as long as you continue to get Kerbin altitude survey contracts. Not only does it save you the need for a full redesign as the game progresses, but since it travels at 600m/s, these survey missions go by faster and feel a lot less tedious. There's still a place for combo jet engine/rocket planes, especially for part testing contracts where you're looking to reach far beyond 20km, as well as eventual SSTOS, but sometimes MOAR JETS on a lightweight body is all you need. I've written a bunch in this post, but the main takeaway is managing your TWR can squeeze a lot of performance out of seemingly unimpressive plane engines and parts. Link to full Imgur page with picture annotations
  4. Some tips that might help with the porpoise issue: Make sure the rear landing gear touches down first Decrease the angle of attack on your wings once you land, either using flaps to force the plane downwards or even by arranging the landing gear so the wings are angled down (ie taller landing gear in back - makes more sense on space shuttles that take off vertically) Locating the rear gear just behind the center of mass, which also helps with takeoff Higher brake percentage in the back and lower in the front (can also do this with friction control) Try to get your vertical descent speed to be less than 10 m/s, ideally even 5 m/s when touching down Consider pumping the brakes instead of locking them on Make sure your landing gear setup can bear the weight of your aircraft without being bouncy (e.g. sufficient landing gear size/quantity and using struts to reinforce wings and other parts to which the gear is attached) Took me ages to figure out how to land a plane I recently designed using MK III fuselage and F.A.T. 455 parts and the above worked for me (it even works for landing on uneven surfaces such as Kerbin's Highlands)
  5. I had a "oh now I get it" moment after doing a bunch of research and testing on wheel settings in career mode, and here's my attempt at the post that would've saved me some time: Friction Control: Varies the amount of friction between the wheels and the ground. You can think of this as changing out different sets of tires with varying amounts of grip. Higher Friction Control: The wheel is less prone to sliding, slipping, and spinning out, at a tradeoff of the craft being more likely to flip over during a turn (the wheel becomes more likely to lift off the ground when rapidly changing direction since it doesn't want to skid). Higher friction can help keep a vehicle in place when braked on an incline. It can also help keep wheels from spinning out in low gravity environments (lower gravity = less downward pressure on the wheel, for which higher FC can help compensate). Lower Friction Control: The wheel is more likely to slide, both front to back and side to side, and hence a craft with low FC may be more likely to spin out than to flip over. It can also make your steering-enabled wheels less responsive (they slide a little in addition to turning), which helps keep a rover stable at high speeds by preventing overly tight turns. Wheels with lower FC are less responsive to acceleration and braking as well. Tips: Having a higher friction control on the back wheels (with steering disabled) can prevent you from spinning out Having a lower friction control on the front wheels (with steering enabled on the front and not the back) can prevent you from flipping over while trying to steer at high speed (effectively makes your wheels less responsive to steering without enabling advanced tweakables) You may need higher friction control when driving up and down steep inclines or on low gravity surfaces UPDATE June 2023: Per the third link below (and my testing), while counterintuitive, you actually want to lower the friction control when driving on low-gravity bodies. While you may want to compensate for the low gravity environment (which imposes less downward force on the wheels) with more friction to make your vehicle more responsive to acceleration and breaking, you also make the vehicle more likely to flip over when turning. First priority in a low gravity environment is generally keeping your wheels on the ground in the first place when driving, and low friction control helps you do that at the cost of lower responsiveness. Consider combining tweaks to brake percentage with tweaks to friction control when trying to keep your planes from spinning as you land/brake More of a brakes thing, but remember that KSP doesn't have anti-lock brakes, so if you're spinning out while breaking try pumping the breaks rather than holding them down Traction Control: Lowers the motor output to a wheel if it is spinning faster than the vehicle is moving. It's like the traction control in cars. The Drive Limiter function lets you lower the amount of power the motor is outputting to the wheels Higher Traction Control: The motor will put out less torque as a wheel meets/exceeds the vehicle's speed. This can prevent a wheel from spinning out (no torque for you until you match the rest of the vehicle!), but tends to lower motor output for the wheel overall. This lower output can also use less electricity per wheel on average when traveling. Lower Traction Control: The motor will continue to provide higher output as the wheel approaches/exceeds the vehicle's speed. This can make a wheel more prone to spinning out (overcoming its friction with the ground and sending your rover flying out of control). Lower traction control can help a vehicle on steep inclines (as it delivers more power to the wheels) or if a vehicle is stuck. Tips: Pay attention to electricity resource consumption and the "Motor" status gauges in the wheel right click menu to get a better sense of what Traction Control is doing to your vehicle Unlike Friction Control, Traction Control only affects your vehicle if you're using the motor. If you're powering your vehicle with jets, rockets, or rotor blades, Traction Control isn't relevant Dev Blog References here, here and here Hope this helps, and if I missed something important/got something wrong, please chime in!
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