Help much appreciated parsing these....
37a What will happen aboard the 11.13? (5) - EVENT (What will happen)
I don't if it's relevant but 11d is INSECT REPELLENT and 13a is RAPSCALLION
28d Tiring complaint about drink being sour (8) - EMBITTER
Is it ME BITTER?
39d Installed candle-holder, drilling final piece (9) - ENSCONCED (Installed)
51d Take rapid steps to get ex-president back from America (5) - POLKA (Take rapid steps)