Confutus

Design, build, fly, and test. Heavy on the test. Report #7 1) Science: Bob was able to successfully navigate the Slugbeast SJ to collect Goo, temperature, and pressure readings at the flagpole. 2) Aircraft testing: 2a) Single engine. Mothra 1d, 3a, and 4 were taken for 45% thrust runway tests. Mothra 3a lifted off from the runway at to an altitude of about 10 m and was successfully brought to a landing on the beach. Mothra 5 at 30% thrust reached 30 m/s Monarch 1 at 45% thrust reached 46 m/s but did not take off. Monarch 2 at 20% thrust reached 17 m/s Bombyx 1 at 20% thrust reached 41m/s, continuing to exceed expectations, but showed a tendency to oscillate with yaw and roll while still on the ground. 2b) Twin engine: Apis 1 at 15% thrust reached 21 m/s Apis 2 at 15% thrust reached 22 m/s and showed a tendency to yaw in one direction. Apis 3 was build and tested at 10% thrust reached 21 m/s and showed even more tendency to yaw in one direction. Bombus 1 was build and at 10% thrust proved nearly uncontrollable. It yawed severely, failed to respond to control, and lost an engine to ground collision. Vespis 1 was built and tested at 10% thrust and reached a runway speed of 15 m/s before cutoff. 3) Unmanned probe: Splitmunk 2 was fitted with two batteries and a baromter and launched with a “Flea” booster. 2 pressure readings were transmitted. There was insufficient power for a third. 4) Rocket testing: 4a) Single stage: The “Reliant” engine was tested with 80% fuel and reached an altitude of 1885 m. 4b) Two stage: a “Swivel engine with a 400% FL-T100 fuel was launched toward Danfrey’s Awe. Jeb began the pitching maneuver too soon, and the rocket toppled into horizontal flight at an altitude of only 1200 m. Jeb attempted to cut thrust, decouple the engine, and engage the parachute, but failed to accomplish this in time and was killed. Nevertheless, Wernher and Gene pressed on, with Valentina as the sole surviving pilot. 4c) Three stage test. 3rd stage Mark 1 command module. 2nd stage Double FL-T 100 tank, “Terrier” engine. 1st stage Hammer SRB. Dubbed Long Jump 2. Valentina failed to engage the SAS on launch, and the rocket began to topple from a vertical trajectory. She attempted to regain control with only limited success. She then attempted to decouple both engines, but they did not separate, and continued to propel the Command module in horizontal flight. She also deployed the parachute, but even after the “Hammer” booster finally cut off, the “Terrier” engine continued to boost the command module in near horizontal but descending flight. Finally, at an altitude of only 700 m, the second stage finally separated, and the parachute brought the command module and Valentina to a safe landing. This second disastrous failure immediately after the first tragic loss was a demoralizing setback for the program.

Design, build, fly, and test. Heavy on the test. Report #6 1) Science: An attempt was made to gather remaining science data at the flagpole, but this attempt did not succeed, so Bob went on to the R&D facility. There was enough data from this and the flight above the atmosphere to qualify for “Advanced Rocketry” R&D grants. Since there are plenty of parts in plenty of combinations that have not yet been tested, we will not be pushing this aggressively. 2) Aircraft testing Single engine: 40% thrust test runs of the Mothra 1d, Mothra 3a, Mothra 4, and Monarch 1 were mildly disappointing; these reached 48 and 40 m/s runway speeds, but did not fully lift off before the designated throttle cutoff point. The successful flight with an earlier version of the Mothra 1 used more runway to achieve enough speed to lift off. Without SAS, Mothra 1d and 3a, which had been straight-running craft, veered off the runway, so this test was considered unsuccessful. A 20% thrust test run of Mothra 5 also veered off the runway. All the vehicles that veered off the runway were braked to a stop successfully without damage, which was one of the goals of these low power tests. A reversed landing gear version of Mothra 1d, dubbed Bombyx 1 (for the silkworm moth) was tested at 10% thrust and reached a surprising 29 m/sec runway speed. Monarch 2, a type C wing version of the longer fuselage Monarch 1, was tested at 10% thrust and reached 17 m/s without incident. Twin engine: Apis 1 with the control surfaces damped slightly was tested at 10% thrust. It did not show the troublesome yaw oscillations, but it was over-sensitive to pilot course adjustments. Apis 2 at 10% thrust reached 17 m/s runway speed without problems. These include the Apis 3 with wings extended using type E boards; The Bombus 1 (named for the bumblebee, not to be confused with the Bombyx) based on the Apis 1 with a reversed landing gear. The Vespis 1, an extended body version of Apis 1. This last begins to resemble the EZ Trainer described by the famous flight mechanics expert @keptin although the version he described has a different tail configuration and more advanced parts. The pace of design is exceeding the pace of testing, so Wernher von Kerman has declared a moratorium on new designs. 3) Unmanned payload testing The Splitmunk probe was modified by placing the parachutes further down toward the body of the “Flea” SRB. A battery was mounted in the Service bay. This achieved an altitude of approximately 10.9 km. Two temperature readings were transmitted to KSC. This was not new science, but it proved the concept. 4) Rocket testing 4a) Single stage testing, the “Reliant” LFR with a 60% fuel load reached 1042 m altitude. 4b) Two stage testing: A 350% fuel (FL-T100 tank) test of the “Swivel” engine sent toward Danfrey’s Awe reached an altitude of 15 km, which was not quite high enough to complete the intended contract, and not enough distance from the KSC. 4c) Three stage testing: 3rd stage Mark 1 command module. 2nd stage Single FL-T 100 tank, “Terrier” engine. 1st stage Hammer SRB. Dubbed Long Jump. Achieved an altitude of 11.5 m at SRB cutoff, a maximum altitude of 85 km and enough distance to reach Sector NVC9, although it was in a different direction. This was our first flight test of the high altitude “Terrier” engine. Future tests will modify this version for longer range suborbital flight.

How about all of the above? My ascents to orbit are woefully inefficient. I haven't yet launched a craft with enough Dv left over to try transfers, rendevous, or docking. A whole planet is about as much precision in landing as I can manage. I can build an airplane that will take off and fly, and I can steer to the vicinity of marked targets, so that's probably my best skill. Aircraft landings I can walk away from are still iffy. I need moar practice.

Design, build, fly, and test. Heavy on the test. Report #5 1) Science There was enough Science gathered from around the complex to qualify for the “Flight Control” R&D grants. Gathering of science data has been somewhat haphazard, as new instruments have become available. Crew Report and EVA observations are now complete for all facilities at the KSC. Goo, temperature, and pressure observations are needed at the flagpole and R&D facilities. Materials study is needed in most locations. 2) Aircraft Runway tests of the various aircraft continued, with 35% engine thrust runs for Mothra 3a, Mothra 4, and Monarch 1. Mothra 3a’s nose wheel lifted off at 37m/sec. A new swept-wing vehicle, Mothra 5, was built and underwent a 10% engine thrust run, reaching a top speed of 15.9 m/sec. A thrust cutoff policy is being strictly enforced. Although it is very tempting to go ahead and fly, we want to be able to practice landing the craft without leaving the runway. Landing in other places can and will be practiced later in the development program. Apis 1 was given another 5% engine thrust run. The problem with veering off the runway was corrected by adjusting the orientation of the rudder tailfin, but another developed: The craft yawed back and forth, even at the low speed of 5 m/s. This is thought to be due to feedback induced oscillation in the SAS, and more trials will be conducted to see if reducing control authority of the rudder helps. This is also thought to be related to the pitch oscillation noted with Mothra 1 and may rehabilitate that series. A new design, Apis 2, with the type C structural wing used for Mothra 1 was built and given a 5% thrust run. This achieved a top speed of 4 m/s. Although everyone is impatient for actual flight tests, it is better for such control issues to show up and be solved before leaving the runway rather than in the air. An outside consultant @Fierce Wolfobserved that the nosewheel was mounted backward on some designs. Although this appears to be mostly cosmetic, the change can be made. He also recommended that in future designs, the forward and rear landing gear be switched. This one of several ideas already considered for testing and will be tried, but a complete halt to the existing program when several vehicles are already so close to actual flight testing was thought unnecessary. He also recommended a complete redesign of all landing gear with an appropriate test program, but LightYear Tire Company which makes the wheels objected that it was beyond their means. "Maybe in another universe, but not this one!", he was heard to mutter. 3) Unmanned payloads The Splitmunk probe was fitted with a 2Hot thermometer and launched with a 300% small tank fuel load and Swivel engine. Without SAS capability, it showed a tendency to deviate from the straight vertical flight plan. Although ground control attempted to compensate, the rocket tipped over and began spinning wildly out of control with 50% fuel remaining. The flight was aborted and the engine and fuel jettisoned. There was an attempt made to read the thermometer and relay the data, but the on-board power of the probe was insufficient. It is thought that the unstreamlined nature of the Splitmunk led to the loss of control. Until R&D can produce a appropriate adapter parts to minimize ascent stage drag, probes will be tested at low altitude using the “Flea” SRB. 4) Rocket testing. 4a) Single stage. The Airhammer vehicle with a 50% fuel load and 22% thrust, estimated Delta v of 929 m/s sec reached an altitude of 10.4 km. The Thumperjumper with a 30% fuel load and 21% thrust reached an altitude of 9.4 km. Simulations indicate that going much higher than this bears a serious of risk of instability. On descent, aerodynamic forces may put the vehicle into an uncontrollable nose-first dive. The single-stage testing of SRB’s is therefore terminated until new engines are available for testing. A “Reliant” test was inadvertently omitted from the program in this cycle. 4b) Two stage. This testing was postponed. This will be resumed with an emphasis on longer range flights. 4c) Three stage. With a bare Mark 1 command module 3rd stage, a second stage with a fully loaded medium tank powered by a Reliant engine, and a first stage of a fully loaded Hammer SRB, an attempt was made to launch Jebediah above the atmosphere. The flight was a complete success, and reached an altitude of 124 km before descent. With a descent velocity of over 1100 m/s, there was noticeable re-entry heating beginning about 30 km, but the module was designed to tolerate this and slowed to around 260 m/s before the parachute was deployed and brought Jeb to a safe landing on Kerbin’s grasslands. This fulfilled a major contract and brought in significant funds. It was decided to upgrade the astronaut complex, to allow EVAs off Kerbin’s surface.

It's the one in report #4. I don't seem to be able to get both sets of wheels pointing the same way. On the 4 wheeled ground vehicle, the editor insisted on flipping the front pair back around when I rotated them 180 degrees, so I gave up fighting it and let it have its way. The nose wheel was another problem. That's really finicky to set going straight manually and the snap setting didn't want to do it in the forward direction. (I've think I've managed it now, but it took some fiddling. As long as it's going straight down the runway... ) And yes, they are rather bouncy. I see that I can set the friction on the wheels, but does this first tier of wheel parts even have spring and damper settings? I couldn't find them.

I've done enough tests with different models of vehicle that I don't think its a landing gear problem. You can't see it in the picture, but the rear landing gear is spread just wide enough to give me a free degree or two on the AoA while still on the runway. The CoM is close to and ahead of the CoL, and both are close to and ahead of the main (rear) landing gear. I'm also flying at about a 10% fuel load in engine tanks and empty main tanks because I don't need more for runway tests and short hops around the KSC. One model has gotten into full flight at 40% engine thrust. I expect others to follow soon. A couple are lifting the nose wheel already at about 38 m/sec, before crossing in front of the SPH building, and without touching the pitch control, so I think I'm good with with these issues. What concerns me is the oscillation in attitude before I even leave the ground. I have pitch on the one hand, yaw on the other, and why not roll, too? This appears to be highly sensitive to details of vehicle configuration and speed. It appears in some models but not others, and it could be due to interaction with the SAS; one more thing to test. It may either go away or get worse with increasing speed. If it persists in flight, it's an invitation to a crash. I don't think this is a typical beginner problem, although it could be one of the many factors contributing to the high crash rate among beginners. Most beginners don't take the cautious, finicky approach to flight testing that I'm doing. I didn't, when I started, and I've been told it's not The Kerbal Way. But that's precisely why I'm doing it.

I see information about veering off the runway, but not wobbling while still on it, not in the FAQ or either tutorial.

I've noticed in a 5% power test of my Apis 1 aircraft (shown here ) that it goes yawing back and forth as it goes down the runway at a blazing 5 m/s. I know this isn't a landing gear problem, since other vehicles with identical gear configurations go perfectly straight. It's aerodynamic. The rudder tail fin can be seen swinging back and forth as SAS enters a cycle of overcorrecting first to one direction, then the other. I've already encountered a similar problem with pitch, so I expect it can occur with roll as well. Whenever and however it occurs, it can make control of the aircraft difficult. Pilot input at just the wrong direction at just the wrong time can deliver compelete control to the laws of physics. I have the idea, based on what I remember of the physics of vibration and resonance, that I can simulate damping by reducing the control authority of the various control surfaces. To save time in testing, is this an effective approach?

Design, build, fly, and test. Heavy on the test. Report #4 1) Science The Slugbeast S had a ScienceJr 9001 added to its rear and two battery modules so that full reports can be transmitted. This version was renamed the Slugbeast SJ. The power supplied by the jet engines can recharge the batteries, but the process is slow. 2) Aircraft. The 25% power trials of Mothra 3a, Mothra 4, and Monarch 1 were unremarkable. These all reached runway speeds of about 30 m/sec without lifting off. A new craft, Apis 1, with a short body like the Mothra series, but twin engines mounted on the wings and a conventional tail (horizontal tail fins for elevators, and a vertical tail for a rudder) underwent a 5% power runway test. This craft had a tendency to yaw to the left, a problem that will need to be fixed before undergoing tests at greater power. This version may never see much use. Engineer consider that forward placement of the elevator tailfins was necessary to move the CL forward enough to balance the craft near the CM, but will probably make pitch control more difficult than it ought to be. 3) Unmanned payloads. A Probodobodyne Stayputnink was placed on a Service Bay with a Communotron 16-S antenna inside and a pair of side mount parachutes. This was dubbed the "Splitmunk" This was placed on top of a "flea" booster and launched to an altitude of 6944 m. The probe successfully reported its existence but returned no scientific data and returned intact to the ground. Manned rocket testing. 4a) Single stage. A 40% fuel trial of the "Airhammer" vehicle reached an altitude of 4911 m. A 20% fuel trial of the "Thumperjumper" reached 4987 m. A trial of the "Reliant" engine with a1 small fuel tank at 50% fuel reached 794 m. 4b) Two stage tests. A command module with a"Swivel" engine and 250% Small Tank, oriented toward Danfrey's Awe, reached 5.9 km altitude. 4c). A command module, a 200% Small tank on a swivel engine, and a Flea booster reached an even 10 km altitude. A command module, a 100% Small tank on a swivel engine, with a fully fueled Hammer" reached a record altitude of 37122 m.

Design, build, fly, and test. Heavy on the test. Report #3 1) Science. Bob got a batch of science from the Tracking station. The program qualified for "Basic Science" R&D contracts. 2) The Mothra 3a, the Mothra 4, and the Monarch 1 were all tried on runway tests at 20% power. Jeb was especially impressed by the Mothra 3a. Wernher Von Kerman wanted a 50% test of the original Mothra 1, and its variants, but Jeb and Val refused. 3a). The Mark 1 command module atop the Hammer SRB, dubbed the "Airhammer" was tested at 30% fuel and 17% thrust, Delta V of 615 m/sec, reached an altitude of 4662 m. A Mark 1 module atop a "Thumper" SRB was dubbed the "Thumperjumper" and tested, but the switch to deploy the parachutes was miswired and the parachutes deployed on launch. The rocket failed to reach 200 m, but the already-deployed parachutes brought it to a safe landing. The test was repeated, at 10% fuel and 14% thrust, with a Delta V of 364 m/s and reached approximately 1100 m altitude. The vehicle was recovered safely. The test of a Mark 1 module atop a "Reliant" LRB with 15% thrust and a 40% fuel load was computed to have a delta V of 265 failed for the same reason as the Thumperjumper. The same tech committed the same error and was fired for it. A repeat of the test reached 460 m; dangerously low, but Jeb survived the test. 3b) The separable "Swivel" with 2 small tanks of fuel was fully loaded and sent out over the ocean, tilting its trajectory at 45% to the vertical. The command module was fitted with a 0.625 heatshield for testing at splashdown. This test was successful and fulfilled a contract. 3c) A 3 stage vehicle was tested. Third stage was a bare Mark 1; second stage was a 1 tank "swivel", first stage was a "flea" SRB. The flight plan was to roll the ship while the first stage was boosting to put it on the correct heading for Danfrey's Awe, and then pitch the second stage toward it for a high altitude observation. The test failed when Jeb performed a yaw instead of a roll and sent the ship on a near horizontal heading well below 5 km. The second stage appeared not to fire correctly. Jeb jettisoned the stage and landed the command module. Since this was pilot error, the test was redone. This time everything worked correctly, but there was too little fuel to reach the minimum altitude needed for the contract. Payload testing can now begin. It has been observed that the placement of the CF behind the CM which works well to maintain attitude on ascent turns into a disadvantage on descent. The aerodynamic forces acting at high speed may overwhelm the controls on the command module and force it into a nose down attitude. Since this lacks the aerobraking effect of the usual nose up attitude, the craft then goes plunging at high speed into the ground. At high speed, parachutes may fail to deploy or be ripped apart if they do. This cannot be allowed, hence there is a need for careful payload design and testing.

@Laie Wow. Funky. Very Kerbal. I never would have dreamed of something like that.

I am indeed planning to include tweaking the angle of incidence, further along in the flight test program. First, I want to see what happens with straight wings of various sizes and configurations at various throttle settings. There are a lot of variables to play with; it's more systematic to change only one thing at a time.

Design, build, fly, and test. Heavy on the test. Report #2: 1) Science. Bob gathered a crew report and an EVA from the Flagpole. 2) Aircraft testing. A 40% power run on 3 variants of Mothra 1 had mixed results. On the first test, Jeb maxed the throttle instead of shutting it down. By the time he got it right, the craft went out over the ocean. It was going so slow in an attempt to ditch it that an attempt to bank went the wrong way, and it plunged into the ocean, still going about 27 m/s. Jeb survived, but the plane was a loss. The second variant was still going too slow at the designated throttle cutoff point. The third showed the least porpoising, going 46 m/s at the designated cutoff point. This vehicle will be taken as the new baseline for further tests. Mothra 2 behaved similarly. Mothra 3 lifted off so smoothly that Jeb was in the air before he knew it. He belatedly cut the throttle and landed safely on the runway, near the end A variant to be called Mothra 3a was designed and built but not tested. Another variant to be called Mothra 4 was designed but not built. This one will extend the wings using Type E wing connectors. The first of a new series of craft to be called Monarch 1, which has an extended fuselage, was built but not yet tested. 3) Rocket testing. 3a) A Mark 1 capsule atop a "Hammer SRB" fueled to 20% and held to 20% thrust reached a top speed of 110 m/s and an altitude of 2342 m. A test of the "Thumper" SRB was postponed due to safety and overspending concerns. A test of the "Reliant" engine was also postponed. 3b) Measurement in the VAB revealed no significant different in weight or fuel capacity between two FL-T100 tanks and one FL-T200; Which is preferred seems to be a matter of part count and convenience in attaching fins. A single stage LRB sent a Mark 1 command pod over the ocean to gather a crew report and EVA of Kerbin's waters. Based on simulations, there was some fear that tilting as far as 45 degree angle to the vertical would cause the rocket to lose control but apparently it was going fast enough that the SAS and aerodynamic forces compensated. 3c) A three stage rocket with the second and third stages consisting of "flea" boosters with the thrust set to a TWR of 2 achieved an altitude record of 31, 517 m (in the upper atmosphere), a speed record of 250 m/s and due attempt to turning the flight of the second stage to a 45 degree to the vertical, set a distance record of over 10 km. Sufficient funds were obtained from setting these records to continue the testing program with new parts.

But I like doing things the hard way. Sure, I could build high performance craft with starter-node parts, but I really don't like to crash and burn umpteen dozen times before I get something that works well enough to use. That's more frustrating than fun. It tickles my fancy to learn how to control my creations at something like the same pace I am learning to build them. If I'm doing something edgy I can always go to sandbox mode, blow stuff up, and kill kerbals to my heart's content and call it simulations, but I prefer the challenge of developing things with limited resources.

Design, build, fly, and test. Heavy on the test. This is another career mode game, unmodded KSP 1.8.1 with "Making history" and "Breaking Ground", and reverts and respawns turned off. The goal is to develop an aerospace industry with planetary, orbital, and interplanetary components and methods. The emphasis is on development of safe, reliable, economical craft even if desirable scientific progress is delayed. Fuel is cheap. Parts and vehicles are more expensive. Dead pilots are really costly. Report #1 The program is in the early stages. Joining it in progress, there are three parts: 1) Science. Bob Kerman, chief scientist, operates the Slugbeast S; a jet propelled ground vehicle designed to gather scientific information around the KSC. This is thrust limited to a velocity of about 10 m/s and has two pair of wheels for stability. Thermometer and barometer are hidden on the right hand side of the vehicle. 2) Aircraft. The aircraft division is intended for the design and test of, well, aircraft. Jebediah Kerman and Valentina Kerman alternate as test pilots. We are currently doing runway tests of what we have named the Mothra series, with minimal fuel loads and increasing power each run. The first version tested, the Mothra 1, can fly, but is prone to porpoising as it accelerates down the runway and repeatedly stalls after initial liftoff. There are several variants with different placing of fins, engine, wings, and rear wheels, in order to attempt to reduce the porpoising and stalling behavior. The Mothra 2 is identical to the Mothra 1 except for addition of elevators to the tailfins. The Mothra 3 is identical to the Mothra 1, except that it uses Type B Wing connectors instead of Mothra 1's Structural Wings Type C. The Mothra 3 has been most successful so far. 3) Rocket testing. This at present has three sub parts. Jeb and Val alternate as test pilots for this program. 3a) Single stage testing. This involves attaching a module directly to the engine and recovering the entire craft. Testing involves partial fuel loads to determine height and range with differing Delta v. For solid fuel rockets, testing of the "Flea" SRB is essentially complete; the "Hammer" SRB has just begin, the "Thumper" is available but not yet tested. For liquid fueled rockets, the "Swivel" with one small tank has been tested and successfully recovered. The engine bell is comparatively fragile and requires multiple parachutes to land without damage. Small FL-T100 tanks can be stacked and larger FL-T200 tanks have become available. Which configuration is preferable will be tested in the VAB. The "Reliant" engine is available but not yet tested. 3b) Two stage testing. This involves separating the command module and the engine with a stack separator. This is little different from single state testing at lower levels. On the one hand, this involves discarding the engine and tanks in flight and is significantly more expensive than the single stage. On the other, as rockets become larger and heavier, the survivability of high velocity and high altitude single stage craft becomes questionable. As revenue from completed contracts comes in, the two stage program will become more important. 3c). Three stage testing. Calculations and simulations indicate that these craft will be able to reach space and Low Kerbin Orbit and return. We envision an extensive program of high altitude, high speed, and long distance testing with various configurations. We anticipate that once we have qualified for the Basic Science R&D grants, there will be a fourth division: Payload testing, with unmanned and manned versions.