I found this Gem on the Cancelled Aircraft Facebook group

very limited information exist on the aircraft, it was a 2 seat delta wing with a fan pusher configuration from the mid 1970’s

Only 2-3 protypes where built before the project ran out of money.

Beyond the out of funds issue, it looks like a real clean design and if the construction & flight qualities where really dialed in it would have likely done well.

The folding wings & tail would have been a huge selling point.

Looks like it could be a real speed demon.

There is a good history written up on Reddit: https://www.reddit.com/r/WeirdWings/comments/dsw64v/rohr_2175_fan_jet_a_ducted_fan_delta_wing/

There is an out of print book about the 2-175 that may come up on e-bay or if you setup some kind of notified search.

Working in aircraft propulsion most of my career for the 1970’s era, a conventional pusher setup like a Long Eze would have done better, I do see a little bit of 737 Max contentions at play with the ducted fan its a much smaller diameter than a conventional prop, this gives it centerline thrust and very short landing gear. In the modern era there are some gas turbines that would likely do well with this configuration. Taking on a unique engine and airframe at the same time is a game of many will enter, few will win.

While a pusher can offer better visibility and “ramp apeal” a tractor configuration usually wins out in the end as most aircraft regardless of configuration need concentrated mass in the nose, not the tail and Tractor aircraft are way better at cooling particularly on the ground. With a Nose wheel configuration, a prop strike is not a factor like it is on a pusher. And like in cars an engine in the front usually provides better crash protection than an engine in the rear.

With this in mind the Dyke Delta 9/19 aircraft of the month, & Verhees D-Plane 12/23 aircraft of the month have lived on still flying today in several flying examples both have conventional tractor configurations

There are some YouTube videos on the 2-175

1st one wont let me embed it but you can click the watch on youtube link in the screen

I know from RC aircraft that delta wing aircraft if designed correctly can be Steller performers with a very high strength to weight ratio structure due to the short, thick wings. The glide ratio is not as good as a long aspect ratio conventional aircraft and can loose energy in a turn however the natural lighter wing loadings often help mitigate some of these flight qualities.

My original Moth (green) was powered by a Norvel .061 and logged a ton of flight time, it is a very reliable with predictable flight qualities. I had a ridiculous armada of RC planes to chose from with much larger, more advanced back in the day however my Green Moth was usually the go to.

2nd one was the E-Moth (blue) built around the time when 3 phase electric motors and lipo batteries first started becoming common in the mid 2000’s. Electric propulsion is more dialed in now to it would be worth it to try out a 5″ racing drone motor on it.

This one is the Climax Delta from RCM Plans, it was also another RC aircraft that I racked up alot of time on, featured a K&B engine with a factory tuned pipe

Plans are still available on outerzone = https://outerzone.co.uk/plan_details.asp?ID=5875