AeroGav

It is quite a lot draggier than an intake or a proper nose cone, so the "ideal" is to use a nose cone on front and some kind of inline clamp o tron further back, but in practice the mk3 fuselage parts you have there (esp. cargo bay) will dwarf the drag produced by your nose cone. Your arrangement is aesthetically pleasing and easier to dock with. If you end up needing more liquid fuel, you can make some tailbooms out of big S strakes instead of the Big S fin (which holds no fuel) ... but i agree the fin part looks better. What do you have on the back end ? Is that a mk3 engine mount or a mk3 to Kerbodyne adapter ? You need to choose a low drag method of engine attachment. The Kerbodyne adapter has one Kerbodyne sized attach node on the back which makes a lot of drag if something with a different sized attachment face is stuck to it - such as RAPIER engines. Or, if you used a mk3 engine mount (space shuttle lookalike), you need to remember that this has a central 2.5m node as well as the three RAPIER size ones. If this 2.5m attachment point is ignored, or has something with a wrongly sized attachment face stuck on it, it too makes drag. So, if you're using one of these, put a 2.5m tricoupler on that middle node (you'll probably want to offset the other engines outward a bit to make room) and give yourself three more engines. Like I said previously, I like the mix of panther and rapier. Why tricoupler, and not bi or quad? Well, the bi only has slightly less drag than the triple, whilst the quad has nearly twice the drag, so it's kind of the sweet spot. Example of a 6 engine config - Or Simplest of all, you could just drop that mk3 mount for a mk3 to 2.5m adapter, then go straight to a 2.5m triple mount (can always stick more engines on the wings if you feel you need more). Bear in mind this adds rocket fuel to the back end of your airplane, which will make it tail heavy on takeoff and a potential lawn dart when empty. So you will want a short mk3 rocket fuel fuselage in front of the cargo bay to balance that out - which might be too much fuel for a vessel this size.. but I suppose that's not a bad problem to have. Above all else folks, remember, this three way adapter, with a 1.25m on the top and three 1.25m on the bottom, is incredibly draggy But this one, with a 2.5m node at the top and three 1.25m on the bottom, cleaves the air like a teflon dart

Thanks for the picture. I'm surprised it flies at all ! 1. Too many engines, too many fuel tanks, not enough wing for the massive weight this thing must have 2. Too much of the airplane's dry weight is at the back of the ship. You can see the yellow ball is at the back of the cargo bay. All of the cargo and most of the fuel is in front of the yellow ball. When these are gone the airplane will be very tail heavy. 3. The tail fin should be as far back as possible so it has more leverage 4. Pitch controls are very close to the centre of mass. This might correct itself if you can move the CoM forward a bit, or you will need to add some canards. As for drag... Fuselage generates most of the drag in KSP. I suspect that due to the poor flying qualities of that airplane, it is only able to get enough lift by pitching the nose far above prograde and is only able to maintain control by operating the control surfaces at large deflection angles. I suspect this is especially the case at high altitude. The Space Shuttle style engine mount at the back of the main stack has three 1.25m engine attach points, which you are using, but it's also got a single 2.5m attach point in the middle. Unused attach nodes create a lot of drag in KSP, it treats them like a missing nose cone (pointing forwards or backwards is the same in KSP), also all joining nodes must be of the same size, eg. you have to attach something with a 2.5m mating surface to this unused node to avoid the drag penalty. So you can either a) Put a 2.5m tri coupler on the unused 2.5m mode. and move some of your wingtip engines to the extra mounts this gives you eg. like on this or b) say goodbye to the space shuttle engine mount altogether, and fit a mk3 to 2.5m adapter instead, with a 2.5m triple mount behind that

I think both options would be towards the rear of the craft overall, being just in front of the engines which are the last part on the main stack. https://imgur.com/Kllc9ED Whilst it is true that drag at the rear of a craft can stabilize it, it is much better to use lift. For example, the big S strakes i turned into vertical stabilizers here, have zero angle of attack and generate little drag when the craft is following prograde. But if any sideslip develops, this gives these parts and angle of attack and they produce sideways lift that torques the tail back into line. I have found that drag chutes are helpful when landing on Duna (stops the plane spinning out and flipping on rollout) but you don't want to add drag when flying to orbit !

I am assuming that you are using RAPIER engines. 1000 m/s is not fast enough for rocket mode. Rapiers can get you to 1400-1500 in level flight in airbreathing mode. Level off at 17-21km for your "speedrun". Once the acceleration starts to die down, switch to rocket mode and pitch the nose up gently so that it's pointing 5 degrees above prograde. For the loss of control problem, i suggest installing the mod called RCS build aid. It shows a red ball in the SPH which is where your CoM will be when the tanks are empty. It could be that you have more fuel at the front of your ship than at the back and your CoM is shifting rearward, causing instability , later in the flight. Alternatively, your engines are not in line with the airplane's centre of mass. This can happens with engine pods mounted low under the wing or above the fuselage - and as the air gets thin, the torque from the off axis thrust overwhelms the aerodynamics. RCS build aid helps with this too, it gives you a torque number which you can try to minimise. Finally, you can make it easier to make small adjustments to your flight path (you need to be gentle at very high speed) by right clicking on control surfaces (Especially pitch / roll control ones) and using the "limit authority" slider. When flying to orbit you never want more than 10 degrees pitch anyway. You can also use the fine rotate tool on your canards/tailplane so that the airplane cruises with a slight nose up angle (2-5 degrees above prograde) with SAS off and no control input from the pilot. You can do that by trial and error by making a few short flights lasting less than a minute. Makes the plane less hard work at high speed

Define "screws up". Goes out of control ? Overheats ? Accelerates but runs out of fuel before getting to orbital velocity ? Plunges back towards the ground ? Or simply fails to accelerate ?

Generally all the fuel you need for airbreathing parts of the flight can go in wing parts and intakes - remember you can turn big S strakes vertical and use them as vertical stabilizers, because they will stick out far behind your CoM and have a good bit of area, they are very effective at surpressing sideslip. OTOH, I prefer to solve the problem by just going liquid fuel only. That requires a heavy emphasis on high lift, low drag, and on getting as much fuel into wing parts instead of fuselage ones as possible (wing parts produce less drag than liquid fuel fuselage tanks of same capacity and of course the lift is a bonus), as well as making sure the craft is stable and controllable enough to fly an accurate AoA (drag doubles with every 2 degrees you move off prograde). https://kerbalx.com/AeroGav/MK1-Griffon-Deep-Space-Crew-Shuttle 40 ton mk1 inline cabin with 11 seats, 2 nerv 1 rapier 1 pantherslightly larger liquid only shuttle - Its not so easy to work into larger ships because the size adapters between mk3 and 2.5m only come in rocket fuel format

Best airbreathing combo in my opinion is one rapier and one panther per 50 tons of launch mass. Erring to the low end (say, 35 tons) will allow a bad design or ascent profile to get supersonic, but increases the risk of running out of fuel. Panthers are light and have the strongest thrust subsonic and transonic. After mach 2.5 they quickly lose power, but by that point the Rapier will be pushing very hard. But surely it is better to have an all RAPIER setup ? Well, the thing is you'll need more engine mass to get supersonic, and your top speed in airbreathing flight, so long as you're not climbing, won't be that different. As you get above mach 5, RAPIER thrust falls away rapidly What's the best launch profile ? In my opinion, if you're looking for max delta v/payload fraction, it's 4 stage process 1. Initial climb at subsonic speed to get out of the soupy lower atmosphere. Speed below 240, nose not more than 5 degrees above prograde. 2. Level off to go supersonic, above 440 m/s, start to climb again 3. Level off again at 16-21km for the speedrun. You're looking to get at least 1350 m/s airbreathing 4. Once the rockets are lit, pitch up so the nose is 5 degrees above prograde marker, this gives the best lift drag ratio and the lowest overall drag losses Alternatively, will help you find the best altitude/airspeed relationship for your aircraft. Finally, something that's not been mentioned yet - I'd loose the pointy cockpit. They tend to overheat when flying the most efficient launch profile. Switch to an inline cockpit for less stressful thermals.

I would take neither, the 1.25m bicoupler is very draggy. Funnily enough the 2.5m bicoupler and tricoupler make far less drag. But, in a mk1 design i'd just attach type b nose cones or ncs adapters either side of the main stack if i only wanted 2 engines, and have a nose cone on the back of the main stack.

Built my highest delta V spaceplane ever, for a trip to Tylo. The panther decouples, and eventually , so too do the whiplash boosters. Booster separation goes off without a hitch, and the aerodynamics of the upper stage are such that it is able to cruise to orbit through a combo of wing lift and the meagre thrust of 5 nervs. Unfortunately, what I had made, was Tylo Impactor Deluxe, a vessel that augers into the body with an impressive fraction of its launch mass, should you desire a Viking funeral for one of your Kerbals. TWR is below 1 even if you empty all the tanks, and of course Tylo has nearly as much gravity as Kerbin, without any atmosphere those wings can use. Do'h!

I'm going to go against the grain here and say, "no". A well optimised stock airplane can have a lift to drag ratio of over 4:1, and hold that from mach 1.7 upwards to orbital velocity. Ferram Aerospace makes it much easier to bust mach 1, so long as your airplane is suitably swept like a real supersonic fighter. The lower atmosphere is much less soupy. However, after mach 1.6 or so, lift to drag ratio continues to decrease with increasing speed. By mach 4 or 5 it'll be falling below 2. That is because it does not model compression lift, which was used on the XB70 Valkyrie (mach 3 cruise speed) and AFAIK all current hypersonic concepts. Now, if you are building a chemical fuelled SSTO, the limiting factor on how much fuel/payload you can burden each engine with is based on your ability to bust the sound barrier. Once in rocket mode, you have so much thrust you can pretty much ignore drag - if worst comes to the worst, zoom up like a rocket and get out of the atmosphere, then finish accelerating unburdened by drag. I you're building a low TWR nuke engine space plane however, hypersonic Lift to Drag ratio is EVERYTHING. [Stock Aero : Our TWR is only 0.36 to 1, but we have a L/D of 3.5 to 1 so we can still claw our way upwards. 7800 dv, woof.] I would say that it is easier to make a low drag FAR plane than a stock one though. Just use common sense, or copy a real fighter jet, or turn on the area rule plot and just rearrange stuff to make a smooth line. Stock aero is counterintuitive, hides its logic from the player, and tends to produce ugly, unrealistic looking aircraft. I'll go out on a limb here again and say "no". I've seen a wide variety of designs, but i've never seen a mach 1.6+ airplane that has a landing speed below 70 m/s. I suspect that much of what FAR does is simply to use Voxels to calculate how "swept back" your overall shape is, and use the degree of "sweptness" of your design to reduce the low speed lift and high speed drag. Of course, this is realistic, but the price of your easy sound barrier busting is that if your re-entry is misjudged and you find yourself coming down over terrain other than the perfectly flat space centre peninsula, the landing is not going to be survivable, sorry. Stock aero, you can make an SSTO with the low speed flying qualities of a Fieseler Storch. Ludicrous, but also fun.

Optimum lift to drag ratio is about 5 degrees angle of attack at supersonic speed and 2 degrees at 100 m/s... think the transition is pretty linear. For the approach from orbit, i usually aim my reentry to hit the ground in the desert continent west of the space centre, then i hold somewhere close to optimum lift/drag angle on re-entry (5 degrees) until it looks like i might overshoot, then start pitching up to a steeper angle (10-15) degrees. In terms of final approach to runway, it's usually just a screaming nosedive with a pullout then some sharp manuvers to try and bleed off all the speed that built up in the dive, followed by a landing somewhere on the same postal code of the space centre due to overestimating/underestimating the energy needed. So long as you put it down without damage in the right continent, that's enough. If by some miracle the screaming dive was not needed or you're landing off-airport and aren't bothered about landing in a specific place, a stable glide on the last few hundred metres is best i think. Glide in at 4 or 5 degree AoA and gently flare to landing. More than 5 degrees on the approach there is a risk you won't have enough energy to flare, you'll either hit he ground at high sink rate or you'll get too high AoA and tail strike. Once you get above 10 degrees angle of attack there is not much lift to be had from pulling harder just a whole bunch of drag. If you're reaching 10 degree AoA and are not <2 second from touchdown its time to panic. OTOH if you only have 2 degrees aoa on the glidescope you're coming in very fast and the "float / flare" part of the landing could last a very long time on a slick airplane. You may end up landing several miles further ahead of where you thought you were going (plenty of my spaceplanes have ended up touching down at water's edge when i was aiming for the west end of the runway)

@septemberWaves I tried to recreate your lower stage airplane then graft my "scream chaser" upper onto it. The hardest part was making the two subassemblies merge in SPH - the attachment system can be such an ass. https://www.dropbox.com/s/2u6gj1c8b35j3y3/piggyback.craft?dl=0 The scream chaser upper is indeed heavy, but it's got plenty of lift and not much drag (the SRB only takes it up to 10km & 440 m/s , it has to cruise on to orbit from there with 60kn of nerv power). In a shallow climb, your upper stage gets it to mach 5 air breathing no problems. However, it starts pitching up when the RAPIERs go to close cycle mode because there's lots of thrust below the centre of mass of the combined vessels, especially as the lower stage gets light when all that LFO is guzzled away. For the second test flight I was going to correct this by angling the RAPIER nozzles a bit in SPH, and was planning to test this out in rescaled Kerbin system, but I realized i'd probably misread your intention so stopped work. I was assuming you were using a flight manager/stage recovery mod so you can fly both halves of the airplane after separation, but i think your goal was to accomplish this without any mod, and just get the lower stage zooming up at steep angle, so that you've got time to circularize your orbit on the upper stage before the lower falls below 35km and is auto deleted. In that case, both stages need really high TWR and nuke engines don't make sense, nor do large wings on the orbiter. KSP adding "fake difficulty" here. https://www.dropbox.com/s/2s8t3ix76nha50j/Almost FlyingWing.craft?dl=0 Also, I had another attempt to make a satisfactory stock flying wing SSTO, but once again i chicken out and stick on some tailbooms. To balance the fuel in the tailbooms, requires from front mounted strakes. Still, there is not much fuselage to this thing. The main stack consists of a fly by wire hub, a mk1 command pod, a service bay, a nerv, and a panther. It actually has enough fuel left over to reach Duna, so i started thinking about how to make it land on Duna without busting apart. The main problem with landing an airplane on Duna is the tendency to spin out then flip when encountering rough terrain, so i tried to engineer in lots of "understeer" to the landing gear. The main legs are much larger than the nose, and the friction control is set to max on these and min at the front, also the rear gear are quite far behind the CoM. This is something you are advised not to do, especially if your plane has no canards, since it makes it hard to push the nose up and take off, but i was desperate to get as much "understeer" as possible. On Kerbin, it is indeed unable to lift off until it hits the ramp at the end of the runway. This is exacerbated by it's nose down stance on the ground , due to the rear gear legs being longer (i wanted to maintain penty of clearance at the back, since the other way to damage your airplane when landing on Duna is to tailstrike when trying to land a bit slower). I put an oscar b in the service bay and a vernor thruster on the nose, which doesn't help it lift off on kerbin but does work well on Duna. Finally, belt and braces approach, we have some braking parachutes. The drag at the rear of the airplane keeps it going straight on rollout no matter if you hit a bump. This appears to work, i did a quick save just above landing on Duna. My first attempt resulted in the nose strakes busting off (i didn't deploy the chutes), but the next three were all good, no damage landings, with various degrees of grace. Work needed - this thing is not yet KerbalX ready. It's got a natural tendency to pitch up to 7 degrees with SAS off, which is a bit too steep at any point on the ascent from Kerbin, though is a good landing approach attitude on Duna. If you try to remedy by selecting prograde hold, it then pitches down to 1.5 degree AoA, which doesn't give enough lift in the airbreathing flight. The controls are a bit too sensitive to correct these tendencies easily. I should probably reduce control authority on the elevons and add some trim flaps to make it easy to control climb angle precisely on ascent.

The overwhelming majority of drag comes from fuselage tanks in this game. 2.5metre tanks have good capacity to drag ratio, mk2 tanks have the worst. I made a comparison of different size tanks here - However, Big S wing tanks are the best for drag vs fuel. I recommend you swap all your aero surfaces to big S ones if possible, and keep your fuel for the air breathing phases of flight in these - do not add mk1/mk2 liquid fuel tanks for jet fuel, and definitely do not haul LFO tanks around with the oxidizer emptied ! I recommend you get the mod Kerbal Wind Tunnel, it will show the best height to attempt to bust the sound barrier. For example, with one of my more marginal designs, the performance envelope looks like this - This airplane most easily passes mach 1 at 7km, it cannot do it right down at sea level. At 16km it reaches almost 1600m/s. Drag doubles with every two degrees you pitch the nose above prograde. For high speed flight, you want to be able to limit the angle of attack to 5 degrees. Your design might benefit from more wing area - this will allow it to fly higher, where the fuselage produces less drag, without having to pitch the nose more than 5 degrees above prograde (which also causes drag) in order to get sufficient lift. Finally, I would consider swapping half of the RAPIERs for Panthers. The Panthers are much lighter, but give more thrust at low speed. The Panthers will quit at 800 m/s, but by that stage your rapiers are so strong with ram air boost, you can get by with 1 rapier per 60 tons of ship.

About a year ago I sent you a craft file for a two stage to orbit vehicle for your upscaled Kerbin system, though at the time i think it was only 2x stock and now you're at 3.2. The orbiter stage had 3 NERV engines, kept most of its fuel in the big S wing parts, and had a droppable Whiplash engine on each wingtip. TWR was only 0.5 to 1 so it relied on the lift from its large wing area, because it skimmed the atmo all the way up, there was also a lot of heat so it needed inline cockpits. Perhaps similar techniques could increase performance of your orbiter. Could the RAPIER stage of yours carry the orbiter stage of my Scream Chaser design ? It's got about 6000dv, though even that isn't quite enough for a RSS scale i fear.. https://kerbalx.com/AeroGav/Scream-Chaser

Ah sounds like you're making a Delta V Heavy / Falcon Heavy, with core stage throttleback. For the normal Falcon 9 full thrust, would using a Vector for the booster stage and a Terrier upper stage approximate the thrust and isp differences between the two stages, while keeping stage diameter constant ?

I think it is easier to design a plane to be naturally stable, than it is to fight SAS for control. Use RCS build aid to make sure your engines are in line with centre of mass, so that the plane does not pitch up or down as engine power changes. Also use RCS build aid to make sure your centre of mass is the same with empty and full tanks. Be generous with vertical stabilizer area/and try to put as far behind centre of mass as possible - this gives it more "leverage". Dihedral/Roll stability is difficult. I only trim for pitch, and make manual roll inputs to keep the heading at 90 degrees East. In theory Dihedral should give roll stability, but i've never been able to make an airplane that flies to orbit without some manual corrections to level the wings. The problem with Dihedral on a conventional airplane layout is that it makes the wing sections act more like vertical stabilizer, but as the main wing is ahead of centre of mass, this can end up reducing your yaw stability. However, if you have a canard / delta configuration, perhaps you can put dihedral on the outboard and rearmost wing sections. This will cause the dihedral sections to be aft of CG and not reducing yaw stability. However, most unwanted rolling appears to come from bugs in the physics engine not aerodynamic reasons. For example, if you attach engine nacelles either side of the main fuselage and then attach wings to the nacelles, this can cause problems in some KSP versions, as can importing craft built on earlier versions of the game. Attaching the wings directly to the fuselage, or simply reattaching parts again without changing anything, or adding struts, can fix this.

Are you flying with SAS on ? SAS conflicts with trim inputs, preventing the desired effect. It sounds like you already know how to fly an airplane with pitch trim, but i made a tutorial video last year showing the method. I don't turn SAS on till over 41km - and two seconds later the engines are shut down as we coast to Apoapsis. Make sure CC / Subtitles are enabled on Youtube so you can see the comments, I don't actually speak :-)

Oxidizer, Schmoxidizer. Make Liquid Fuel only SSTOs and conserve that precious HTP for it's true purpose.. dyeing Kerbal hair blonde/pink/red. No good Jeb, that thing's too small for the peroxide crew.... THAT's better..

On a winged ssto, this is incredibly easy because you don't need twr over 1. Even more so if jet engines are allowed. My KerbalX shares include a 1 Terrier, 4 juno ssto , and numerous panther/nerv liquid fuel only ssto. I have also built a Juno nerv winged ssto which worked, though wasn't particularly capable. Poodle is not a small engine. It is a beast ! I made this ugly career mode thing with a Poodle and 2 Panthers, lifted a Science Lab to orbit with gobs of fuel to spare I am not the master though. That title belongs to this guy - NERV from sea level to orbit, no jet engine or thruster of any other kind.

https://kerbalx.com/AeroGav/Monstrosity-225L Liquid fuel only , no oxidizer. Does this only work for small SSTO? Well, this one is quite big actually. 6 Panther, 6 Rapier (air breathing mode only), 12 NERVs to keep the cabin warm. Bubble cockpit provides good view of the sky but not so good over the nose, parking may be difficult. .

I think it's best to update the first post in the thread as I didn't read all the posts before starting something. I spent a couple of hours on it trying (once again) to come up with a satisfactory vertical launch spaceplane. No air breathing engines. The orbiter itself has a pilot and ten passenger seats. a NERV under each high mount wing. The main boosters have Reliant engines fed by a pair of FT800 tanks strapped to the sides of the NERV nacelles. The Reliant stage is not recoverable. It does not have the TWR for vertical launch however, so the first few seconds are assisted by a pair of Fleas. The Flea stage have parachutes on them and jettison so low that they can land before the airplane goes out of physics range. Won't save much money, bur it's something. The fleas boost us to an incredible 44 m/s and 160m altitude.. Reliant power for the masses. You can see the separatrons on the nose of the boosters. They yaw the nose outwards and downwards on separation, which causes aero forces acting on the body of the booster to push it further outward and down. The boosters get us to an altitude where the NERVs can work well, and through the sound barrier, but that's about all. It's not easy to build something out of multiple Big S wing parts that still looks ok. Dry wings would mean i need cylindrical tanks to store the fuel which would add drag however. Safety Features There is a ballistic recovery chute mounted to the upper fuselage. The abort button could be triggered to lower the landing gear, release the chute and fire the separators for all boosters. Between the recovery chute, ability of this craft to glide, low stall speed, landing gear , 40 m/s impact tolerance of crewed parts, and the crumple zone surrounding the crewed stuff, loss of all propulsion should be fine whether it happens 3 seconds , 30 seconds or 3 minutes into flight. There is an inline clamp o tron ahead of the cockpit, which can be used to transfer crew to another vessel should the orbiter have a fault that prevents safe re-entry. However it is not outfitted with an RCS system which precludes routine use. The orbiter would simply rendezvous with the rescue vessel and passively allow a full translation space tug dock to it. Design Issues, work in progress I really hate seeing wings go unused during the ascent, such a waste of mass ! In this vessel's case, the lift to drag ratio they have enables it to fly to orbit with a TWR under 0.5 , so long as the booster gets it to 400 m/s and 8km altitude. In turn, the low TWR requirement means we can use hyper efficient NERV engines, and put most of our fuel in the wings. The biggest issue is that the orbiter stage, under nerv power, flies at a 5 degree angle of attack with the nose about 7 degrees above the horizon, for perhaps a 2 degree climbing angle. The booster prefers a 30 degree climb angle and of course launch with the fleas is vertical with TWR > 1. Fairly aggressive maneuvering is required. Below 100 m/s in the booster phase it wants to lawn dart so full back stick, then it starts wanting to pitch up more and more due to the lift , and towards the end of the booster phase you need to start flattening out the climb angle to something more suited to flight on NERV power so you're banging the stick forward. The wing is mounted high on the fuselage to make room for the boosters, which means most of our fuel is above CoM. Causing a pitch up effect from the NERVs. If you climb at too steep an angle, you'll get into a low dynamic pressure regime (high and slow) and this becomes quite noticeable. If you climb more shallow aero forces surpress that tendency. When circularising it can really pitch up a lot if you bang the throttle open abruptly. Flight tips As I say, key is to not let it lawn dart after launch (pull up), then nose down as needed to keep climb to no more than 30 degrees. Above 7km start to push the nose down to a shallower climb (10-15 degrees). Once on NERV power, try to take SAS off and keep it off as long as you can to minimise drag. It is aerodynamically very stable but the torque from the engines likes to push the nose up a bit. Use pitch trim to maintain climb angle - ALT + S key. To begin with, you'll be halfway up the pitch trim scale to get a 5 degree AoA, as you get into the upper atmosphere, you'll be winding this off as torque from engines is pushing the nose up plenty all by themselves. https://www.dropbox.com/s/gwh3fx2dn6xjkwh/EXPRESS2.craft?dl=0

As you don't drive, the thing you might not realize is that even normal driving, within speed limits, obeying the laws of the road, keeping under 0.5g or whatever, is fascinating. It is more complex than any video game, so much stuff going on, so many cars and junctions to keep track of, gear changing, rev matching, an infinite map to explore. If you really want to experiment with stuff that falls outside of those limits, have a track day, take an advanced driving course, go go-kart racing, or just play GTA V There are far more paranoia inducing things than insurance black boxes these days. Automatic number plate recognition cameras everywhere, any day you could get a "penalty charge" notice in the post, because you exceeded the speed limit by 1mph or had 1 wheel in a bus lane for 1 second at 2 am when driving along an unfamiliar, poorly signposted road. "Crash for Cash" fraud. Every time you take your car in for its annual safety inspection and the garage tells you it needs an expensive repair to X, do you trust them ? Etc.

UK has a lower accident rate than just about any other country in the world - it's safer to be a driver here than in US, Germany etc by a factor of two or more. However, the accident rate among young male drivers has been slow to fall, despite introducing a large theory component to the driving test with "hazard perception" test videos. However, I read the real problem with young male drivers was once they got their mates in the car with them ... one up, they were fairly safe. There was suggestions of banning new drivers from carrying other young people as passengers. However, I heard that these "telematics" black boxes, that spy on your driving and report G forces and speeds to your insurance company in real time, have had a dramatic effect on these young drivers (they've had less effect on older ones) What I suspect is happening, is that it allows the driver to resist peer group pressure to do stunts when his mates are in the car. In my day, refusing to do any of that stuff would have them thinking you are too boring, too chicken, or too unskilled to try a bit of racing or drifting. Young people understand money however, they don't have enough of it and they want to spend it on clothes, music and beer. You can just point to the black box and say "rather spend my money on beer, sorry" and your friends will get that. One reason I heard for UK's high insurance premiums is due to the way injury compensation for passengers of vehicles in a collision is paid by the insurance company. In the USA I think the medical insurance system or state ends up picking up the tab.

It's a mystery to me how in the UK, (similar to Poland, I expect) young drivers are regarded as a menace, if you're under 27 you'll be paying over £2000 a year for insurance on a 10 year old car with 65HP. I took my driving test at 17 but couldn't afford a car or the insurance till i was 27. Yet in America, you can drive a small block Chevy at 16 with God knows how much HP .. how are the roads not littered with dead teenagers? When I was at college, no-one had a car, for these reasons. Then, one of my classmates was able to borrow his Dad's car for the day... no-one the class ever gets to ride in a car that doesn't have their Parents in it.. so immediately all the other lads jump into the passenger seats and start asking him to do stunts... Wheelspin ! Handbrake turns ! I suppose the reason insurance companies try to price young drivers off the road is because sometimes these stunts go wrong. What if he does a handbrake turn, hits a curb and rolls the car ? No-one was wearing a seatbelt... now 4 teenagers will have disabilities for the rest of their lives.. the driver's insurer has to pay out millions in compensation. Back to the overtaking question... In the UK single lane roads have speed limits of 50 or 60mph. The motorway speed limit is 70mph. Honestly, I don't like going 10-15mph faster than the car i am overtaking anyway. If I need that much speed, the gap must have been too small. Before I overtook, my view of the road in front of the slow car was obstructed by it, if you accelerate to 90mph to go past a car doing 50mph, you might suddenly discover a hazard in front of that slow car once you're past him and now you are going too quick to stop. I'm surprised your medical condition is an obstacle to driving. I've known ADHD sufferers who drive. In the UK, so long as you pass the theory test and practical test, and aren't on medication that affects your driving, you would get a licence. The theory test is quite tough now though, there is a hazard perception test, where they show video footage from a car and you have to press a button to identify the risky situations. Like i say though, over here getting the licence is the easy bit...

When I was younger I had a job delivering Pizza on mopeds that were restricted to 30 mph. Also when I was young, I drove a lot of very underpowered cars (could not afford anything better, could not get insurance for anything better, parents would not trust me with their powerful car). I think so long as you know what the car will do, you can make a safe decision about whether to overtake or not. The closest I came to an accident was when overtaking in this turbo diesel car which would accelerate very strongly at first, then the power would rapidly tail off above 2500rpm - you'd start the manoeuvre thinking you'd do it easily, then the power would die off just as you were too far into the overtake to abort. Eventually I got to know the car and to simply not attempt overtakes on single lane roads with a speed limit over 40 mph. I suppose you don't want your auto speed limiter suddenly reducing your car's top speed mid overtake because it thinks you've moved from a 70mph zone to a 50 limit. Still, I don't think accident statistics back up the idea that "power is a safety feature, it lets you overtake more safely", it just makes people take even more risks. If we're honest, the real reason we like power is because it's fun. I'd be happy with a hard 75mph limit, provided the car had some kind of "Head Up Display" (HUD) tech to visualise how much room you need to complete an overtake based on the speed of the car in front and whatever the limiter is set to, so you can decide whether to overtake or just chill.