Percival Prentice with twin fins, any more information?

Take a look at David Gearing’s On the Wings of a Gull Percival and Hunting Aircraft.
There is a section on page 90 dealing with Prentice development; a photograph..

Many thanks for the replies, very interesting, i always wondered why the elevators were that odd shape.

Twin fin Prentice

The twin fin experiment was part of the exercise to try to improve the Prentice’s unsatisfactory spin characteriscs. Alternate tailplane positions were tried , as was the addition of spin strakes ( allegedly copied from a resident Tiger Moth!) and an increase in fin and rudder area which only partly solved the problem. The end result of this investigation resulted in the adoption of the unusual lobed elevators.

Scroll down to #1491
https://www.pprune.org/aviation-history-nostalgia/527527-luton-history-nostalgia-75.html

Brian