Competition Suggestions

[Toxn]

On 9/14/2021 at 8:28 AM, Toxn said:

Someone finally built a pedrail. I've always wondered how these things worked in the real world...

More pedrail:

 

[Lord_James]

6 hours ago, Toxn said:

More pedrail:

 

Are we going to do a competition with wacky mobility gimmicks? 

[Toxn]

2 hours ago, Lord_James said:

Are we going to do a competition with wacky mobility gimmicks? 

That sounds like a fun idea.

It can go into the pile.

[Lord_James]

Can I use this mobility gimmick 

[Toxn]

12 hours ago, Lord_James said:

Can I use this mobility gimmick 

We already had a competition for that 

[Toxn]

Mobility gimmicks:

 

[Lord_James]

Are we going to do a Morman JDB comp next, or are we going back to cascadia to check back on Norman? Or am I just thinking too far ahead? 

[Sturgeon]

4 hours ago, Lord_James said:

Are we going to do a Morman JDB comp next, or are we going back to cascadia to check back on Norman? Or am I just thinking too far ahead? 

 

Next full comp, which will be no earlier than next year, will be a strike fighter competition.

[T80U :DDDDDDDDDDD]

On 9/21/2021 at 2:19 PM, Toxn said:

 

Some new changes have improved how guns work, but we're not at the level of a full cartridge designer yet. Sprocket also habitually under-estimates vehicle mass by 10-15%, which I put down to more or less the same issues that we've encountered in our competitions.

 

I think it's functional enough to build a mini-competition around, though.

I found this on discord

https://discord.com/channels/788349365466038283/788350217304277013

Edited December 16, 2021 by T80U :DDDDDDDDDDD
I read the noobposting rules. There's the link.

[Toxn]

3 hours ago, T80U :DDDDDDDDDDD said:

I found this on discord

https://discord.com/channels/788349365466038283/788350217304277013

I'm on the discord and quizzed them about it a few months ago. I couldn't get a straight answer out of them on how they wanted to implement the cartridge/shell designer.

 

We'll just have to see how it plays out I guess.

[Toxn]

On 11/20/2021 at 2:03 AM, Sturgeon said:

 

Next full comp, which will be no earlier than next year, will be a strike fighter competition.

So I finally got a copy of X-plane 11 (thanks steam sales!) and have been looking through the plane designer that comes with the game (https://developer.x-plane.com/manuals/planemaker/). 

 

Although I haven't fiddled around too much with it yet, it seems to be perfectly feasible to use it to design aircraft for competitions. I had hoped that we could run a competition using paper designs, select the finalists and then build and compare them in X-plane (saving everyone the hassle of all having a copy of the game in order to participate), but looking into the details of how the plane maker works this probably won't be possible.

[Sturgeon]

16 hours ago, Toxn said:

So I finally got a copy of X-plane 11 (thanks steam sales!) and have been looking through the plane designer that comes with the game (https://developer.x-plane.com/manuals/planemaker/). 

 

Although I haven't fiddled around too much with it yet, it seems to be perfectly feasible to use it to design aircraft for competitions. I had hoped that we could run a competition on for paper designs, select the finalists and then build and compare them in X-plane (saving everyone the hassle of all having a copy of the game in order to participate), but looking into the details of how the plane maker works this probably won't be possible.

 

N
I

[Sturgeon]

F
T
Y

[Dominus Dolorem]

If I may ask, how would one go about designing a plane and it's missiles?

 

Which simulation programs will be used?

[Toxn]

17 hours ago, Dominus Dolorem said:

If I may ask, how would one go about designing a plane and it's missiles?

 

Which simulation programs will be used?

The plan right now is to use X-plane, which is a flight simulator that includes a designer function. The designer also includes some stock weapons that you can add - but you can design missiles for it too.

 

The two issues are that X-plane is typically quite expensive to get a hold of, and the learning curve on the plane designer is steep.

[Dominus Dolorem]

5 hours ago, Toxn said:

The plan right now is to use X-plane, which is a flight simulator that includes a designer function. The designer also includes some stock weapons that you can add - but you can design missiles for it too.

 

The two issues are that X-plane is typically quite expensive to get a hold of, and the learning curve on the plane designer is steep.

Does it include aerodynamic simulation?

 

I have an older copy of X-plane on a disk, would that work?

[Toxn]

52 minutes ago, Dominus Dolorem said:

Does it include aerodynamic simulation?

 

I have an older copy of X-plane on a disk, would that work?

That's what makes x-plane unique - it can perform basic aerodynamic simulations and extract a basic flight model out on its own.

 

IIRC, older X-plane models don't work in X-plane 10 or 11.

[Toxn]

Time is a strange thing. A few years ago, I put together a weapon for a competition that was intended to be the ultimate in one-upmanship. The Stumpy was basically an armoured brick, armed with a high-velocity 85mm cannon and four 250mm missiles. The missiles were sketched out relatively thinly at the time, and used a combination of open-source rocket calculators and what I'd recently read about how radar systems worked to come up with something plausible.

 

Flash forward to the present, and I stumble upon a ridiculously detailed article by Iron Drapes on Soviet ATGMs. Besides making me deeply impressed with whoever came up with Metis, this allowed me to connect some dots that I hadn't before. So, in the interests of future competitions, let me lightly re-imagine and flesh out California's most dangerous anti-tank asset:

 

Ultra-Heavy ATGM, Large Universal Body 

 

The LUB missile is an ultra-heavy ATGM (or perhaps an anti-tank cruise missile), weighting in at around 95kg with its launch motor (and 80kg in flight). The missile fits in a 250-mm wide box with its wings and tails folded up, the body being a 20x170cm cylinder tapering to an ogive at the tip. The fins are relatively large, as the missile itself travels fairly slowly (around 200m/s in its sustainment stage, dropping to around 100m/s at the very end of its flight profile). Due to the generous size of the wings, the missile flies at a very slight up angle (about 5 degrees). The missile is also somewhat unusual in not rotating in flight. This is because it has a wing and tail fin setup more common to a small aircraft, with elevon and rudder control. The elevons and rudder are actuated by gas-powered actuators housed in the wing roots, fed off of the gas generator assembly that also powers the engine turbopump and electronics. The missile also features a small set of canard wings to help balance out the moment of lift generated by the main wings.

 

Getting an 80kg missile up to speed is no easy task, so the LUB has a dedicated solid propellant launch motor which mates to the tail of the missile. The motor uses the quasi-recoilless design found on some old soviet missiles, and falls away almost immediately after launch. Once free from the tube, the missile's main engine fires up. Due to some frankly puzzling internal political shenanigans, this is in the form of a small liquid rocket motor burning hydrogen peroxide and kerosene (effectively a scaled-down B.S. 605 RATO unit). The engine produces around 1.3kN of thrust for ten seconds or so, feeding off of two 6.3l oxidiser and fuel tanks (the first ahead of the motor and the second wrapped around it). The engine exhausts directly out of the rear of the missile, and its turbo-pump stage includes a small generator and flywheel to power the electronics.

 

At the missile's heart sits a frankly enormous 190mm shaped charge, capable of penetrating just over 1m of RHA. It can do so because of the generous stand-off distance built into the missile - the shaped charge shoots through the electronics bay, which is hollow in the centre so as not to disrupt jet formation. Near the tip of the missile is a 75mm precursor charge, itself able to comfortably punch through 400mm of RHA. Both charges are set off by a VT fuze buried in the nose, with the charge timing being handled by the flight computer in the electronics bay. In the event that being able to punch all the way an MBT frontally is not needed, the LUB can also be fitted with a 20kg HE payload, roughly equivalent to two 155m shells. 

 

The control scheme for the missile is unusual, and relies on a radio beacon buried in the rear of the right wing assembly. This is picked up by a spin-scan receiver mounted on the launch controller, which allows the controller to work out how far off track the missile is. The controller then sends a command signal back to the missile, which is picked up by a directional horn antenna in the back of the left wing assembly. Both the beacon and command signals can be coded to limit jamming. This also allows multiple missiles to be salvo launched and independently guided.

 

Guidance commands are processed by the flight computer, which uses a pyrotechnically-spun gyroscope to orient the missile. Other sensors include a pitot tube to gauge flight speed. The guidance computer is a marvel of early transistor-era electronics, and is capable of executing various simple flight programs (such as the post-launch program) in addition to its normal operations.

 

After launch, the missile executes pitch up maneuver and a 45 degree roll to bring the wings to level, Thereafter it levels off to an angle calculated to maintain altitude and waits for the receiver to pick it up. Kinematically, the missile can travel for over 6km, although the CEP increases as range increases. One approach to mitigate this is to have a larger antenna and gunner's spotting telescope, preferably raised off the ground. This allows the missile to be used well beyond the range of any possible return fire, which is useful because of how bulky it is. For vehicle-mounted units where the launch angle can be adjusted, the missile also includes a close in "flying torpedo" mode, where the missile flies straight and level at whatever angle it was launched from. This helps to mitigate the inherent minimum range imposed by the LUB's initial flight profile (around 200-300m), but is quite inaccurate and of dubious value given that the system as a whole is built for long-range fires.

 

Besides the HE model, there have also been some thoughts given to creating other variants of the LUB for different roles. The missile itself was originally meant to be modular, with various payloads, electronics and engine configurations being swapped in and out as needed. Presently, the only real use of this capability has been to trial a version which uses a more conventional solid rocket motor instead of the very expensive peroxide/kerosene unit used on the base model.

 

The LUB is a classically Californian product - phenomenally complicated and expensive for what it provides, and saddled with a certain amount of neo-atomic era hubris and corporate nepotism. On the other hand, it effectively performs and end-run around the cycle of escalating armoured vehicle designs (that the PRC was losing), by providing a weapon that can stop all foreseeable threats. It is a demonstration of overkill, with little regard for the concept of "good enough".

 

 

[Sturgeon]

For the record, Flyout was released for Early Access recently and I have gotten ahold of it and it looks like even in its current state it will support the kind of aircraft competition we've always wanted to run. The detail is there, and the judges are able to import files and fly them off against each other. There is a sharp learning curve, but that's never been a problem before!

[Toxn]

Wonderlik! 

 

I've also bought flyout, but haven't had time to do anything with it yet.

 

When are folk thinking of pulling the trigger on this thing?

[Toxn]

Update: I've now played with Flyout a bit, and although it's lacking in a few key features and components I think it will work for a 1950s strike fighter.

 

What would help would be for the competition organizers to provide specs for the engines, gearboxes and props to be used in the competition.

[Dominus Dolorem]

Will there ever be another "modern" MBT contest?

[Toxn]

On 1/19/2024 at 5:42 PM, Dominus Dolorem said:

Will there ever be another "modern" MBT contest?

I'm not sure. Modern MBTs are very popular, but they're also incredibly technical to design and tend to be a bit same-y in terms of their specs.

[Dominus Dolorem]

I think there were enough unconventional designs in the Texas and California contests.

[N-L-M]

A very real question is whether or not we can come up with a competition which answers all the following criteria:

A. Not a rehash - we've pretty solidly covered the first generation of MBTs with the Cascadian competition, and the second generation with the DPRC one. The Texan comp also fits in there to a large extent. "Modern Light Tank" was also pretty comprehensively covered, as was "heavy armored car". 

B. Of sufficient interest to entice at least 3-4 full entries

C. Of sufficient technical complexity to be capable of differentiating entries, but not of such extreme technical complexity to make it unapproachable or unjudgeable.

 

Not saying there won't be more comps, it's been a while since the last one and so people's minds are likely a hive of activity on various topics, but the "winning recipe" for a new comp is currently unclear (to me, at least).