M & D jet receives EASA Type Certificate

On Friday, December 4, 2015 at 2:03:10 AM UTC-7, wrote:
44 all successful starts so far for me Mike.

4% oil is added to the fuel.

I just remember one jet failure leaving a JS-1 in unlandable terrain in the middle of the Navajo Nation last year!

On Friday, December 4, 2015 at 8:55:24 AM UTC-6, Mike the Strike wrote:
On Friday, December 4, 2015 at 2:03:10 AM UTC-7, wrote:
44 all successful starts so far for me Mike.

4% oil is added to the fuel.

I just remember one jet failure leaving a JS-1 in unlandable terrain in the middle of the Navajo Nation last year!

It was actually this year, Mike. And I wouldn't call the terrain unlandable, the glider and the pilot did not have a scratch.

Further to my earlier performance posting I have today received from M+D a copy of the approved certification version of the engine manual. It is only in German which I can't read but I can make out a couple of significant differences to the earlier draft versions from M+D.

1) 2% oil mix instead of 4%

2) Max rpm 97000 rpm but only for 5 minutes. Fuel use 77L/hr. (Fuel consumption and thrust seem to be exponentially related to the rpm.)

3) Max continuous rpm 80000 (= 58% thrust).

The introduction of the maximum time for full thrust is going to reduce the potential range because previous predictions for the JS1 were that the best range would be a single max power continuous climb then glide. I am not sure what the best climb rate or speed for best climb at 80,000rpm are so I can't make a good estimate of the resulting range but I seem to maintain level flight at around 70knots at 67,000 so it must be climbing at 80,000 rpm.

Further to my earlier performance posting I have today received from M+D a copy of the approved certification version of the engine manual. It is only in German which I can't read but I can make out a couple of significant differences to the earlier draft versions from JS.

1) 2% oil mix instead of 4%

2) Max rpm 97000 rpm but only for 5 minutes. Fuel use 77L/hr. (Fuel consumption and thrust seem to be exponentially related to the rpm.)

3) Max continuous rpm 80000 (= 58% thrust).

The introduction of the maximum time for full thrust is going to reduce the potential range because previous predictions for the JS1 were that the best range would be a single max power continuous climb then glide. I am not sure what the best climb rate or speed for best climb at 80,000rpm are so I can't make a good estimate of the resulting range but I seem to maintain level flight at around 70knots at 67,000 so it must be climbing at 80,000 rpm.

On Friday, December 4, 2015 at 8:33:49 AM UTC-7, wrote:
On Friday, December 4, 2015 at 8:55:24 AM UTC-6, Mike the Strike wrote:
On Friday, December 4, 2015 at 2:03:10 AM UTC-7, wrote:
44 all successful starts so far for me Mike.

4% oil is added to the fuel.

I just remember one jet failure leaving a JS-1 in unlandable terrain in the middle of the Navajo Nation last year!

It was actually this year, Mike. And I wouldn't call the terrain unlandable, the glider and the pilot did not have a scratch.

Excuse my memory - I am already in 2016 mode! Yes, the pilot in that case showed extraordinary skill in landing in what I would regard as unlandable terrain! I had always though the simplicity of the jet made them more reliable than conventional IC engines (at least the retractable ones used in gliders). Do we have actual data on reliability?

Excuse my memory - I am already in 2016 mode! Yes, the pilot in that case showed extraordinary skill in landing in what I would regard as unlandable terrain! I had always though the simplicity of the jet made them more reliable than conventional IC engines (at least the retractable ones used in gliders). Do we have actual data on reliability?

It's 50%! Either do they run, or not. Never put yourself in a situation where you can only be saved by the fire-up of a engine while you are out and gliding.