Hardcore realistic F-18 ejection seat (NACES SJU-17) replicas

[NeoEngress]

This is for fellow simmer pilots who are seeking something more serious than regular gaming chairs and racing seats. Hopefully also for DIY enthusiasts who find the NACES too time-consuming to work out. Despite the broad selection of DIY materials and tools, the construct of this seat presents quite a challenge to work on by hand. 

Unlike the ACES II which is mostly sheet metal. The Martin Baker NACES is a combination of both solid chunks and thin pieces of metal, plastic and organic materials, each requiring its best suited means of fabrication. 

Take the seat bucket side wall above, a piece of thick aluminum plate needs to be milled down before it's bent to the right angles on a multi-ton bending machine. Screw holes are then tapped and had right lengths of steel thread inserts planted within. 

 

Cloth had to be selected with the right texture and color which closely match that of the real seat cushions. Sourcing straps of the right texture is another difficult task. Once the fabrics and filling foam are ready, it takes industrial grade cutting, forming and sewing equipment to piece them together. Snap buttons have to be riveted in place before the back cushions can be filled and closed up. Spring loaded harness retractors are customized with the designated model of straps. Velcros need to be sewn onto certain sections of straps so they can be secured or detached from the headrest, which by itself, is a dense foam that requires a special process to manufacture. 

 

Sheet metal is used throughout the seat. Large sheets of aluminum are laser cut, riveted with clinch nuts or threaded studs and bent into 3D shapes as designed.

 

The different metal pieces are then joined together with various types of rivets, forming very robust assemblies. 

 

Another way of forming sheet metal is stamping. The back pad, seat pan and the top cover of the chute container are stamped out of steel sheets between custom made molds with tons of force from a hydraulic press. 

 

The result after thorough powder coating in matte black. 

Rubber has proven to be another difficult material to work with in a home DIY setting. 

Getting the helical color patterns to match the crisscross texture isn't good enough, the colors have to stick and endure sustained use of the ejection handle. 

Besides individual parts and stiff assemblies, the seat also depends on a collection of moving mechanisms to function. In a real jet, the pilot needs to adjust his sitting position in order to get the correct line of sight. This is achieved through the seat bucket actuator. A 2000N electric cylinder is incorporated in the main structure just for this purpose. The cylinder runs on 24V DC power, preferably with a 5Amp max capacity.

 

The power supply is sourced separately, while a section of power cable is supplied with the seat. It comes with a pair of circular plugs which mate with the receptacles behind the seat. Height adjustment is commanded through the flip of a toggle switch mounted on the left of the seat bucket. 

The retractors for shoulder straps are spring loaded and can actually pull back on the straps. They are not actively actuated by default though. 

 

Kinematic models are used to verify the movement of each mechanism before finalizing the design of linkages and handles. The resistance of the shoulder harness control handle is adjustable through a screw cap on the top. All the handles are operable and internally linked to optional electronics. You can even actuate the sears and have the spring loaded plungers pull out. Check the following video for how they work:

 

When it comes to the ejection handle, I feel your pain in making the repetitive Ctrl+E work with DIY electronics. Sometimes a few extra line of code is enough to hinder the progress by days for the lack of required experience.

As much as we love Arduino, we prefer to build every PCB in our products on our own. That means we design all the PCB's for ourselves, and write all the firmware for ourselves. PCB assemblies are then made by professional plants to ensure proper quality. The switch box on the left side distributes 24V power directly through output cables. Some analog electronic tricks are used on the PCB to tap into that same 24V output without frying up chips, while allowing the firmware to determine whether and which way each of the toggles are flipped. 

Writing firmware from scratch allows us to make the seat show up on the computer as anything we want. In this case, it appears as a generic game controller with a number of buttons. The following video demonstrates how these buttons can be configured in DCS World:

If you find it pointless to assign exactly the same virtual handle functions in game to the physical handles on the seat, you're welcome to get creative and find other uses for them, at the end of the day, they are only generic buttons. Bear in mind the ejection handle is the special one, it is hardwired to trigger three quick and consecutive button strokes to activate the ejection process in game. All possible scenarios such as pulling or pushing a handle from its resting state, or quickly switching it on and off are anticipated while coding the firmware. Noise from snapping mechanical contacts is also properly debounced to eliminate runaway issues in all branches of program execution. 

 

This seat is now on sale for $2,890 at our official site: https://www.neoengress.com/naces-ejection-seat . There're a bunch of other cool stuff on other pages to indulge your curiosity if it's new to you. 

The USB interface, switches and signal cabling requires an additional $360. If anyone is interested in this product, please feel free to write to us at info@neoengress.com for more information, because currently it's the only way to place orders. 

[GenIIX]

Thats some hardcore stuff, machined and everything, wow

Very Impressive

 

[JCook]

Decent price for all that.