Several glo-powered models flying well.

Then trouble.  Poor idle,  premature engine cuts,   all models affected,    each flight worse than the previous one.

Changed to a new bottle of fuel. Same brand, same mix.  Problems disappeared.

The heading picture is my attempt at an explanation.

The SM74 has had two more flights.  Not flying as well as expected.  The above-target wing loading doesn't help [26 oz/sq ft]. There could be other factors. Development required.

Some good flying weather in recent weeks. Models flown include   Lohner   Canberra    B52    Liberator    P38   .