It’s about time to get that hatch done. For months we have been debating and sketching on various hatch ideas and readers of this WIRED blog have joined in with a lot of great ideas. Now, it is time to summarize and get things done on the hatch.
Several ideas on additional hatch procedures have been proposed here at Copenhagen Suborbitals which were not related to the hatch readers gave their best ideas upon. Hatch ideas so far:
The main hatch (which readers presented ideas upon)
This hatch has a very large opening providing necessary access when actually building the capsule and adding the seat inside and it seems difficult to make it any smaller for this reason. However, such a shape and size also gives us the biggest headaches when it comes to pressure and structure. The structure needed to have this opening as an emergency/easy egress system is complex and heavy. Because of this, we had some ideas to use this hatch for ingress only, but never egress which required a different emergency hatch for quick egress scenarios.
Top hatch (main parachute tube), egress only
Center placed in the top of the capsule you have the cylindrical chamber holding the main parachutes. We have discussed the use of this volume if the main parachutes fail to deploy correctly and as a safer opening after normal splash down to avoid flooding of the capsule.
Dynamite-zipper, very much egress only
We just love the idea of cutting/blowing away the top part of the capsule so you are left in the seat in the heat shield. Of course, this can be done even though it sounds completely mad. This is of course a one time only procedure perhaps providing you with a faster and better way to leave the capsule during high speed ascent/descent.
However, the idea of an egress hatch only as an addition to the main hatch was killed Monday night based on the schematic below. So it goes.
So once again left with the large main hatch, which requires heavy complex constructions to open and close from both sides, we have decided to simply “replace” the existing opening by a 2mm steel plate bolted all the way around with as many bolts it takes (perhaps 60 or more). This plate never comes off again unless you have to perform extreme maintenance or remove the seat.
Even if the astronaut was able to have access to all the bolts on this 2 mm plate from inside the capsule he would impact Earth before the last bolt was manually removed, which is why we want to add a circular man-hole (diameter 500 mm) in the middle of the permanently attached hatch plate, opening inwards.
The inwards opening hatch probably gives a lot of readers the shakes, but we believe it can be done with additional safety measures to prevent whatever danger that comes with such a design. Inwards opening hatches are less difficult to create mainly because it works just like a submarine hatch. The further you get on your journey the more tightened the hatch becomes.
This way we can keep our large opening in the capsule for inserting the seat but ends up with a much less complex system for the circular hole used for general ingress/egress but also emergency egress.
The details are not done yet we are not certain to actually create the man-hole for the this first LES-flight. We are still being inspired by the work submitted by the readers! So, thank you all once again.
Ad Astra
Kristian von Bengtson
