The nose is different, as is the canopy, the planform of the ,now low set
wing seems to be different and the tail seems not to have twin fins any
more. The nose wheel could have been the same, but the main gear would
have needed complete re-design, I think. The only detail in common with the
He 162 seems to be the position of the engine. In fact, it reminds me more to
the Arado E.580.
Maybe the designation just means the "Bewaffnungsanlage" (weapons installation),
not the aircraft itself ?
It looks more than an exercise on weapons installation. The bulky nose could mean it is armoured ( not just the SG aperture ), but it would render the pilots visibility a weak one. The wing chord would make it vulnerable, but this "jet shturmovik" is very interesting. Could this be a Henschel project, a successor to the radial engined Hs129?
My question is what is the source of the document? I have done a fair amount of research on WWII German projects and generally (but not always) there would be both a date and an indication of originator's identity on primary documents. If these are known, then a rational attempt could be made to answer question, otherwise SWAG rules.
I thing that graphic Justo has found
Is from Rheinmetall-Borsig Patent to show how the "Bewaffungsanlage" (weapon system) is install into fictional aircraft.
this is SG 118 = Sondergerät 118 based on SG 117 codename „Rohrblock", but installed horizontal for "Heimaschutz" aircraft what became the He 162