Only the fuel tanks attached to rockets have any oxidiser in them. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. You can go above 20km with the J-404 Panther. Building a High Altitude Jet | Stream pt. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Note that you need to activate the afterburner ("Wet Mode") manually. Clear editor. Kerbal Space Program ( KSP) is a space flight simulation video game developed by Mexican developer Squad for Linux, OS X, Windows, PlayStation 4, PlayStation 5, Xbox Series X/S and Xbox One. Or is it the same for all celestial bodies? It only takes a minute to sign up. Slap that behind a plane you'll be able to go beyond 20km without any trouble. If too much air runs into the turbine, the excessive amount just flows out unused through side-vents (I think). Delta wings are able to work better since the lack of lift per square area is compensated by having larger area to provide lift. Hopefully this will be helpful to you. Then it is "In Space Low over Mun.". "Whiplash" Turbojet. (Disclaimer: I've never used FAR myself; all of the above is based on my experience with stock aerodynamics. I did some testing and found that the turbojets get the best Isp around 5.2 km altitude, so I was thinking of flying at that altitude. Then I increase throttle until about 2/3 or even full, climbing with a high inclination (it can also go straight up). As has been said, ISP is nothing to worry about. Did any DOS compatibility layers exist for any UNIX-like systems before DOS started to become outmoded? But you'll need to unlock: High Altitude Flight Which cost 300 science. 1 Pod outside the level 3 VAB. If the wings are flat and your plane steadily loses altitude in level flight at a given speed (as most designs will by default), it means you either need to pitch up slightly, increasing the angle of attack and keeping your vertical velocity at 0 by flying up slightly to compensate for the pull of gravity that lift isn't compensating for. One problem is i'm running stock on career mode and only have 30 part to spare, so large planes are out of the question. All rights reserved. It seems to be based on the General Electric F-404 Afterburning Turbofan, which shares the same name and maximum thrust (85 kN dry). It may work with stock too, I just don't know. AoA itself refers to the angle of the wing (or the whole plane if the AoI is 0)relative to the airflow. Thrust means that slower-is-better no longer applies: now, slower means less drag but more gravity, so there's a tradeoff (which I'm not going to carefully calculate for you, because it's hard). The second, Wet mode, uses the afterburner to produce thrust almost equal to the J-X4 "Whiplash" Turbo Ramjet Engine, but at a considerably reduced fuel efficiency. The Boeing X-37, also known as the Orbital Test Vehicle (OTV), is a reusable robotic spacecraft. There are no requirements as far as size or power are concerned, as the AI Pilot is capable of flying pretty much anything - from tiny scout planes to oversized freight craft. I was even able to do this with three pairs of Junos instead of the large jet engine pair (I don't have the technology level for that). Just sounds like the engines can't get enough air, in KSP high speed also generates air intake so I'm guessing what is happening is that you have the initial speed to get to altitude but the lack of air at altitude is starving the engine resulting in lower speed which further reduces air intake and it cascades until either the engine shuts down or you return to denser atmosphere at a lower altitude. There are two factors to that: how thick the air is, how fast the ship is going. I'm going to try adding a small solid fuel rocket engine toned down to get the initial height then dump it, as well as check into that high end gear mentioned. The longest flight got them down to a little more than half full. I have enough patience to do the slow flying, but is it horribly inefficient? What are the minimum altitudes for each warp level? This means that the only thing that decides wheter your engines run efficient is determined by how much thrust they produce (opt. I also set it to enable the cockpit's reaction wheels to improve control at high altitude, and close air intakes to reduce drag. Air Intake) and how fast your aircraft ultimately flies (air resistance/altitude)! So, to correct " is below crosshairs", what you need to do is to add a little AoA to the wings. Hello there. - but they were talking about having two intakes/engine. Ep. Do plugins for Kerbal Space Program work on unix? The main body is a fuel tank with a Swivel engine at the end. The high performance engine for me performs pretty good till about 15000 meter. The drag differential is because your long-wing layout is using a bunch of struts, and the reason your delta-wing has a higher ceiling is because it has more wing area to provide lift. The J-404 "Panther" Afterburning Turbofan is a jet engine added in version 1.0.5. Thats my problem right now. What are the altitudes for the various altitude record contracts? To get there, you're going to want to climb at the fastest rate you can manage to 18-20 km, at which point you should mostly level off and start accelerating horizontally. Once you're at that regime, you should be able to cover huge distances on tiny amounts of fuel. So I've created those two planes, both with weasley turbofan engine: This is your problem-- as folks have pointed out, it's not a high-altitude engine. So Pvt. I don't have the numbers handy, but you can expect something like 400m/s at 15km. Of course, this thing has very limited range, speed and acceleration because of the extra weight. Approximately 12km up the main engines stop providing enough thrust to maintain the climb, so it's time to switch to rocket mode. I've been trying my hand at some High altitude speedy planes for a while now, but can't seem to get a hang of the altitudes that each engine likes, I know kerbal isn't earth, so looking up the crushing altitude of say the sr71, doesn't seem to apply, but I was hoping that others experiences would help me. 600+ m/s) and low altitudes (e.g. *I use FAR these days, which basically means completely replacing every spaceplane and rocket you ever designed to account for its much more realistic aerodynamics. I don't have that cockpit in my career game yet, but maybe it will work with the other one. 2022 Take-Two Interactive Software, Inc. Even if the air is thin, you can still put out plenty of power if you are shoving enough in with raw speed. . The Kerbal Space Program subreddit. As long a you can fly faster, the lower density at altitude can be compensated for. Minimising the environmental effects of my dyson brain, Theoretically Correct vs Practical Notation. The X-37 is operated by the United States Space Force for orbital spaceflight missions intended to demonstrate reusable space technologies. Been a while since I've flown stock*, but I've heard that, for maximum efficiency, you want one turbojet for every 7.5 tons, and about four ram intakes for each turbojet. How do I install mods for Kerbal Space Program 1.1? As I understand, the OP wanted "the most efficient way to fly", and simply needed a bit of help in realizing that that is a hypersonic, high-altitude, high-performance aircraft which is a RAPIER and a little oxidizer away from being an SSTO spaceplane. Your link has been automatically embedded. Dedicated to the growth and advancement of amateur rocket scientists! Rockets aren t the only way to get to space. Please consider starting a new thread rather than reviving this one. 2022 Take-Two Interactive Software, Inc. These are the building blocks of solid spaceplane design!Subscribe! All other versions are slower and lower and unstable in turns. Which is capable of high altitude, high speed flight. Don't rely on the efficiency indicator! Be sure to have enough intakes (I think maximum efficiency in stock is 1 ramjet intake per ~2 tons of plane, though that is aesthetically ridiculous), and if you're still running short of intake air, you can dip down a bit to speed up and get to denser air. It is usually best for initial designs to be based on logic and real-world physics and then be prepared to experiment with non-logical alternatives for optimisation. The Panther engine can hold 19,000 steady and oscillates around 20,000. 101 kPa 1 atm Scale Height 5000 m Atmospheric Height 69 077.553 m 1.010-6 atm Minimum Temprature -40.19 C 232.96 K Maximum Temprature 20 C 293.15 K Oxygen Present Yes Contents 1 Kerbin 2 Topography 3 Kerbal Space Center 4 Atmosphere 4.1 The Troposphere 4.2 The Stratosphere 4.3 The Thermosphere 4.4 The Exosphere 5 The Kerbin System 5.1 The Mun Kerbal Space Program Jool Landing Youtube. So now to come to an end: from my experience I'd say for a medium sized aircraft it is best to fly between 12-13 km. If your using NEAR/FAR, once you get high and fast, kill the engine and glide to save fuel. Pretty often, the tail "wiggled" and/or the plane became totally unstable when I fired the rocket boosters. With only panthers unlocked I might add. Due to the lower air pressure at higher altitudes its thrust output decreases accordingly. In the main KSP settings menu you should set the default throttle to 1.0 (technically the above mechjeb setting winds up restoring the default throttle, so it needs to be 1.0) In the attitude adjustment menu make sure you are using the "better controller" Whack the 45 degree phase margin button Whack the restore all other defaults button Anyway thanks in advance. How do you get out of a corner when plotting yourself into a corner. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Since turbos are almost always enough to get you off the ground and up to altitude, I usually just do straight turbojets (with some RAPIERs for SSTO spaceplanes); the minute amount of fuel saved during the ascent isn't worth lugging those superfluous engines around at the hypersonic regime. Press question mark to learn the rest of the keyboard shortcuts. Not only does it conk out at high altitudes, but also it conks out at high speeds, and you need to be able to go fast to fly up high. By rejecting non-essential cookies, Reddit may still use certain cookies to ensure the proper functionality of our platform. Note: Your post will require moderator approval before it will be visible. The most efficient way is, of course, to make a high altitude (or space) plane. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Though I'm still working on learning to be better at space planes. To reach the initial low Earth orbit of the International Space Stationof 300 km (now 400 km), the delta-v is over six times higher, about 9.4 km/s. For comparison, the second most maneuverable engine is the CR-7 R.A.P.I.E.R. If you upgrade to the panther (or get one on a contract) that engine can get you much higher. By accepting all cookies, you agree to our use of cookies to deliver and maintain our services and site, improve the quality of Reddit, personalize Reddit content and advertising, and measure the effectiveness of advertising. Thanks for the help! Delta-V is the velocity change necessary to perform orbital maneuvers. You can post now and register later. Use the reaction wheel to hold your attitude slightly nose down as you float down and you can guide yourself like a paraglider. I'd almost expect it to work better in stock since infini-gliders can be done. : : . So long as there's only one high-altitude measurement to take, you should be able to complete a whole set of 3-4 in one flight. I started by attaching two LV-909 rocket engines to a regular low-atmosphere plane: In this save, I don't have custom action groups yet, so I'm using the RCS control to toggle between jet and rocket modes. At about 400-500m/s (~15km), the two engines are even. The more successful the flights, the more successful the space program is. KSP Quick Guides: High Altitude Design and Flying - Stock v.23 Stoober AK 3.32K subscribers Subscribe 21K views 8 years ago This tutorial will cover designing and flying a plane that can soar. Is it correct to use "the" before "materials used in making buildings are"? AoA and G-force moderation. Note: This is ONLY to be used to report spam, advertising, and problematic (harassment, fighting, or rude) posts. Display as a link instead, Unfortunately, there's no simple rule to tell you what the angle needs to be when you're building the plane-- it depends on lots of variables, such as your weight, drag, intended cruising altitude, intended cruising speed. Rationale: If that's all a case of Too Many Words, think of it this way: Suppose you just build a plane the "default" way and don't put any AoA at all on the wings. As said above, the Wheesley is specifically designed as a low altitude engine. What am I doing wrong here in the PlotLegends specification. Once you're at that regime, you should be able to cover huge distances on tiny amounts of fuel. It is stable but can not maintain altitude. Also, while you mentioned the TJs most efficient altitude is ~ 5km (I'm not sure, but lets assume it's true), you need to realize that the drag you're getting at that altitude is going to wreck any efficiency gains. - "In Space Low" means your craft is inside the "Space Border" altitude and in an orbital path. Privacy Policy. 2022 Take-Two Interactive Software, Inc. Make sure we're on the same page with terminology. Create an account to follow your favorite communities and start taking part in conversations. I wasn't expecting so many excellent answers! The Rapier, for example, works great as a high-altitude engine, precisely because it can go so fast. This is my current best hi alt plane. Learn more about Stack Overflow the company, and our products. In addition to the traditional giant tube of explosions that flings things up high approach, Kerbal Space Program includes a very useful piece of equipment that became quite popular in the 20th century: wings.. It may take some practice to hit your target area this way, because you'll be picking up additional horizontal speed, and thus it's possible to under or overshoot. EDIT: Didn't notice you were using FAR. KSP also tends to have very harsh induced drag if angle of attack gets too high. Why is there a voltage on my HDMI and coaxial cables? As high and fast as you can go without engine flameout: preferably ~2000 m/s at 25-30 km (and yes, that's almost orbital velocity). Secondly don't think of engines working better at different altitudes, think of them working better with different air intake quantities. The thrust of jets (turbo or otherwise) depends on airspeed: basics deliver more thrust at low speeds, while turbojets only really come into their own when you fly very fast (which also means flying very high, 20km and over). Your previous content has been restored. You can post now and register later. That's all true, but just read the OP: hypersonic appears to be completely out of the question. Or about the same speed but 1000 m higher. its rather flat but its a solid surface. Unfortunately I won't be able to test it today, but @SaintWacko's proposal sounds promising. This thread is quite old. You can post now and register later. Main goals: Auto-trimming. First is thrust; the higher you get, the lower the thrust your engines deliver. So that means that even if you are inside the atmosphere but still orbital (such as during aerobraking), your science will not count as "Inside the atmosphere", For example, orbiting Kerbin above 250km altitude, your science is counted as "In Space High over Kerbin." But a rockets can do it. Turbojets are so ridiculously efficient that it doesn't really matter. The U-2 is probably the highest altitude aircraft still flying. It is somewhat slow but very steady in flight. New comments cannot be posted and votes cannot be cast. This page was last edited on 22 December 2019, at 20:54. Which makes this engine ideal for those missions which require doing many science activities above particular altitudes. with a thrust vectoring range of only 3 degrees. Imagine that first plane but with the bubble cockpit and the old style round intakes. Powered by Invision Community, Thanks, I'll go try to stuff a few extra turbojets and intakes on my plane, I was generally under the impression that basic jets were mostly deadweight on high-performance aircraft: [] at hypersonic velocities. A well-designed jet with this engine and with the afterburner lit, flown properly, can momentarily climb to 30,000 m altitude. Even up there the plane acts squirrely. Paste as plain text instead, probably the easiest place to land in the system as terminal velocity is survivable for a craft less kerman. Is it possible to get to an altitude of 16-20km with normal plane engines? Make sure you've angled your wings up slightly so that you provide enough lift for a 0 angle of attack at top speed. Your link has been automatically embedded. More air is better. It was meant for low altitude flight. But you'll need to unlock: Which cost 300 science. Immediately starting rocket engines at full throttle turned out to make most of my aircrafts totally unstable, turning them up gradually worked way better. 1.) Welcome to the forums, ZDW. Is there a single-word adjective for "having exceptionally strong moral principles"? Thanks, I'll go try to stuff a few extra turbojets and intakes on my plane Do you know how many intakes/turbojet are needed to run in the regime you described? I don't recall if they model aspect ratio, but either way, the struts are murder and the delta wing has so much more wing that it'll still have more lift. That's sub-optimal, because having the fuselage pitched like that means it'll have more drag than it otherwise would have. A jet engine from KSP 0.18 A jet engine is an air-breathing engine which uses onboard liquid fuel and combusts it with the oxygen drawn from the atmosphere. Technically, any rocket engine is also a jet engine as it forms a high-speed jet of reaction mass. 3x06: I design a new, high altitude, jet to collect high atmospheric science. This lowers their effective "weight"-- for example, a craft flying at 1400 m/s on Kerbin is effectively flying as if gravity were only 2/3 of its actual value. How to make a loop for linear actuator in Kerbal Space Program, Breaking Ground. 2022 Take-Two Interactive Software, Inc. If you enter the Mun's SOI, it immediately counts as "In Space High over Mun" until you get below 60km Mun altitude. Basically you just need to fiddle with it and try some test flights. Espaol - Latinoamrica (Spanish - Latin America), https://steamcommunity.com/sharedfiles/filedetails/?id=1933948095, https://steamcommunity.com/sharedfiles/filedetails/?id=1933948668, https://steamcommunity.com/sharedfiles/filedetails/?id=1934517923, https://steamcommunity.com/sharedfiles/filedetails/?id=1335577943, https://steamcommunity.com/sharedfiles/filedetails/?id=1640213502, https://steamcommunity.com/sharedfiles/filedetails/?id=1640214586, https://steamcommunity.com/sharedfiles/filedetails/?id=1937826505, https://steamcommunity.com/sharedfiles/filedetails/?id=1937931692. To get higher with the low tech jet engines, you need rocket assist. This way control surface max deflection can be programmed by an aircraft designer to make . The ideal case for optimally efficient flight (which is what you want if you're trying to maximize cruise altitude) is when your wings are mounted to the body, pitched up just enough that when cruising in level flight, the body of the aircraft is pointing perfectly . Isn't that backwards snark? How can this new ban on drag possibly be considered constitutional? My 'plane science' is more advanced than my 'rocket science' (career mode) because I got tired of seeing all the high-altitude missions I had on the books and wanted to finish them. 2022 Take-Two Interactive Software, Inc. They will someday, but they don't now. Download (104.45 MiB) License: CC BY-NC-SA 4.0 Game Version: 1.8.1 Downloads: 371,115 Author: blackheart612 Mod Website: Forum Thread Support this mod: Donate Followers: 626 Outdated Mod This mod is not known to work with the latest version of Kerbal Space Program. I'm trying to build a high altitude plane and have found out that the rules are different. Another approach, which I was managing with some success before I figured out jets, is to build a rocket and catapult yourself towards the measurement point. Arqade is a question and answer site for passionate videogamers on all platforms. You can halve the drag by climbing a bit less than 3500m. A well-designed jet with this engine and with the afterburner lit, flown properly, can momentarily climb to 30,000 m altitude. Remember that you need to have intakes somewhere in line with the engine to function at that altitude. a screenshot of kerbal space program 2. by: lord bird. Why do many companies reject expired SSL certificates as bugs in bug bounties? If you have an account, sign in now to post with your account. My plane has turbojets and lots of fuel, but I am wondering what the optimal way to fly is. and our 20 votes, 21 comments. Powered by Invision Community. Grichman's answer got me in the right direction. The Rapier, for example, works great as a high-altitude engine, precisely because it can go so fast. Fighting oscillations. Any of my search term words; All of my search term words; Find results in. Upload or insert images from URL. below 5,000 m), since the engine's extreme maneuverability may allow the aircraft to perform turns sharply enough to break up in flight. You need to do it with what you've got. Range with this method is pretty short due to drag. This causes the body of your plane to generate additional drag. TLDR: You need parts you don't have to make a plane that flies that high. That will unlock: "Whiplash" Turbojet Which is capable of high altitude, high speed flight. In my case, it brought me to 20km up at a 45-degree angle, but it is probably not optimal. Keep in mind that wheesley engine's performance decreases significantly as the altitude increases. Please consider starting a new thread rather than reviving this one. Clear editor. You get tons of thrust if you put it into "wet" mode, but you lose fuel efficiency. In this case lots of fuel is the wrong approach, I can get more than half way around Kerbin on 2 cans of Jet Fuel and a turbojet if I glide most of it. Your link has been automatically embedded. Using very light "engine rich" planes and "reverse swooping" (building velocity at 10km then gently curving up) you can temporarily get above 20km with Wheesely and Juno. Build a plane or rocket for Kerbal high altitudes, We've added a "Necessary cookies only" option to the cookie consent popup, Screenshot of the Week #85 [Submissions Closed - Vote Now!]. I followed a similar strategy. When added to a plane it allows tuning of the controls vs speed/altitude/G load/other factors. Note: Your post will require moderator approval before it will be visible. Whiplash is the engine you would want to use on a plane meant to go 20km. - Insane lift to weight didn't help. at the very least, you'd need the panther, that'll get you over 16k easily, well to 25k. Reddit and its partners use cookies and similar technologies to provide you with a better experience. I only seem to be able to make planes that can fly a bit below that altitude and then temporary rise to it. Let me share what I know about jet engines, speed, and efficiency. Grichmann's answer has been the most reliable way I've found to complete these missions. This is particularly useful for pairs of engines, since this makes it possible to keep the thrust equal when activating the afterburners. How do I align things in the following tabular environment? Mounting a time-limited rescue mission for kerbal inbound to Kerbin. As long as the engine gets enough air it will work at proper efficiency. You are just about at maximum speed and at the same time very close to stall speed. This thread is quite old. 1Altitude requirement 2Orbit 3Speed, range, and altitude 4Flight duration 5Flight profiles 5.1Ballistic missiles 5.2Tourist flights 5.3Scientific experiments 5.4Sub-orbital transportation 6Notable uncrewed sub-orbital spaceflights 7Crewed sub-orbital spaceflights 8Future of crewed sub-orbital spaceflight 9See also 10References I currently have a contract where I'm asked to take crew reports at certain spots on Kerbal at an altitude of 18,000m. A destructible memorial to the old Mk. i recently used a single whiplash plane and was able to maintain a stable 21-22k meter altitude. Note that keeping the plane weight low is critical, only carry a very small amount of fuel. That's because wings need to have some AoA to the airstream in order to generate much lift. So if you want to make a plane go as fast as possible, you want to minimise both angle of attack and angle of incidence necessary to sustain level flight at your target speed and altitude. i dont know what kind of range youre looking for but i would make a significantly smaller plane. Highest and fastest possible is best. Your engine burns the same amount of jetfuel per second regardless of how high or fast you are! Paste as plain text instead, @SaintWacko's advice is probably the most practical. I also added a parachute and decoupler since I find it too hard to correctly land this thing yet ;-) I managed to land in the water once, though. In this chapter, you ll learn about the Space Plane Hangar, a building that forms part of the Kerbal . - "In Space High" means your craft is inside the given Sphere of Influence and above the "Space Border" altitude listed in the Celestial Body Multiplier Matrix. Ksp engine altitudes I've been trying my hand at some High altitude speedy planes for a while now, but can't seem to get a hang of the altitudes that each engine likes, I know kerbal isn't earth, so looking up the crushing altitude of say the sr71, doesn't seem to apply, but I was hoping that others experiences would help me. Or you need to put a little bit of angle of incidence in your wings, which will reduce drag since you don't have to pitch the entire plane up, but will be stuck at a fixed angle meaning you'll have to pitch up or down anyway during certain phases of the flight that the plane isn't optimised for. I'm in career mode (have the turbofan engine) and trying to get some science readings for a mission at a high altitude. To avoid running out of fuel altogether, I have a second plane with small tanks (no oxidizer) attached directly to the jet engines, and the rockets attached behind the fuselage, which is entirely oxidized tanks. Also, Valley and Theomon fly to different corners of Kerbin and three mapping satellites are launched. Subscribe - http://www.youtube.com/c/MikeAben?sub-confirmation=1 Patreon - https://www.patreon.com/MikeAbenPatreon supporters receive early, ad-free, access to videos, kOS and craft files, and more. Discord - https://discord.gg/HTvT7dZ Making Space Home Playlist - https://www.youtube.com/playlist?list=PLB3Ia8aQsDKhqoFyoZ4d33MG7rS9KmDm_0:00 - Designing the Dudley Mk16:42 - Test Flights \u0026 Iterating13:45 - Col. Valley take the Seaplane to the Northern Ice Shelf19:30 - Launch \u0026 Insertion of the Maxwell Vb21:04 - Col. Theomon \u0026 Orlin Visit the Badlands in the Panther24:20 - Launch \u0026 Ejection of the Maxwell VI26:34 - Designing the SENTINEL 129:47 - Launch \u0026 Insertion of the Maxwell VIIFull List of Mods: Aviation Lights Chatterer Community Tech Tree Crew R\u0026R Croud Sourced Science Contract Configurator Contract Packs: Bases and Stations Reborn CommNet Relays Exploration Plus Field Research Kerbal Academy Tourism Plus Contracts Window+ Decoupler Shroud Easy Vessel Switch Kerbal Alarm Clock Kerbal Attachment System Kerbal Construction Time Kerbal Engineer Redux Kerbal Inventory System Kerbalism kOS KRASH Maneuver Node Evolved Navball Alignment Indicator Near Future Aeronautics Near Future Construction Near Future Electrical Near Future Propulsion Near Future Solar Near Future Spacecraft Persistent Rotation Rational Resources RCS Build Aid Continued Restock Restock+ SCANsat Scrapyard SMART Parts Stage Recovery Stockalike Station Parts Expansion Redux TAC Fuel Balancer Texture Replacer Trajectories Transfer Window Planner Universal Storage 2 Unkerballed Start Waypoint Manager The benefits should be obvious. It's Kerbal Space Program v.22! I've since shaved that down more but that was by going even higher and even faster). There is no such thing as "so high radar can not detect it", since radar can detect things in outer space. The other thing to bear in mind is that tuning the AoA (angle of attack) of your wings makes a difference. Any advices for building a vehicle for this task? You are simply running out of atmosphere (i.e. That annoys me but I can't seem to get a design to make it work. I should perhaps start trying out NEAR to get ready of 0.90, though. Air temperatures vary with latitude and time of day. Pasted as rich text. There is a very close tolerance to the two speeds. Note that KSP planes get one substantial speed benefit that's much more pronounced than IRL aircraft, due to the freakishly small planet sizes: they're actually flying at a large fraction of orbital velocity. Cheers again fellas. You can spin around the whole world on just fumes. And how many km can I expect to get per v (as calculated by Engineer redux Kerbin atmospheric stats, I know this is weird with planes)? Kerbal Space Program 2 . Your answer got me in the right direction, though I ended up with a different design (see my own answer). The U-2's published maximum altitude is somewhere above 74,000 feet.