DHN999J is a Dennis Heavy Recovery Fire Appliance based on the Dennis Maxim 30 ton chassis. It is fitted with a Holmes 750 recovery crane. This appliance was supplied new to Durham County Fire Brigade in 1970 and was only withdrawn from service in 1995. It was based at Darlington during its operational life, with most incidents being vehicle accidents on the A1(M) which cuts through County Durham.
It is powered by a Perkins V8 540 engine and is fitted with 2 PTO's, one for the crane and the second for a compressor which works the air cutting equipment. It is still kept busy recovering broken down preserved fire engines. In the above picture Maxim has just pulled back the Operations Support Tender complete with the 1927 little Dennis after the injector pump failed on the Perkins engine of the Shelvoke. Below shows Maxim  being prepared to recover a Leyland Cub Fire Engine!


 

The Holmes crane is a very versatile device. It can be configure with the booms looked together or with the boom separated. An extract from the Holmes handbook shows one of the many configurations.