Airborne muckspreader

A couple of weeks ago the Moors For the Future folks started up the heather brash spreading operations that I've helped out with before. The aim is to spread a thin layer of chopped up heather (brash) over the bare peat as part of the process of getting it to regenerate. In the past the heather has been airlifted by helicopter onto the moors and then spread by hand. This is a very time and labour intensive process, and it is quite difficult to get an even layer. This year they are using a different technique (and a different helicopter company). Instead of the heather being lifted on site and then spread it is loaded into what I can only descrive as an aerial muckspreader which is then flown under the helicopter.

Black Hill helicopter

Here you can see it on the back of the truck - there are a pair of the spreaders, whilst one is being filled the other is being flown over to the spreading area. The bottom of the spreader is a conveyor belt that moves the heather towards the back of the contraption. The two vertical shafts with the disks and tines on them rotate towards the gap in the centre and fling the heather out of the back. The whole thing is powered by a small petrol motor underneath the hopper.

Black Hill helicopter

The lift site was right at the summit of Holme Moss, next to the transmitter tower. Being a peat bog means that even though the ground looked frozen it was actually very soft underneath - as they found out when they tried to drive the truck over to the stockpile of brash bags!

Black Hill helicopter

Needless to say a cooperative farmer and a large tractor were required to hoik the truck out of the hole it had dug for itself and move it over to the bags.

Black Hill helicopter

The helicopter they were using was a Squirrel. They'd taken all the seats out to keep the weight down - each spreader weighs about 1/4 tonne and holds up to 6 cubic metres of brash, so they needed all the umph they could get.

Black Hill helicopter

Unfortunately this meant we had to walk the 2.5km onto the moor, and boy was it cold. The spreading area was directly around the trig point on Black Hill - anyone who knows the area will understand just how bleak it is, and it was pretty windy too, which made it feel all the colder. The mast you can see in the background is the Holme Moss transmitter - at one point this mast provided TV coverage for most of the North West of the UK.

Black Hill helicopter

Once on site two people stood either end of the swathe they wanted the helicopter to cover and the pilot flew over them, turning the spreader on at the appropriate moment. It took about 30 seconds to dispense the 6 cubic meters of heather. The area on the right of the photo has already been covered, and the area on the left is not yet treated. Depending on the height, each run covered a swathe about 5 - 8m wide and perhaps 100-150m long. This was at the start of the day and the pilot was coming in relatively high, by the end of the day he was coming over us at about 2 - 3m above head height.

Black Hill helicopter

Here's a view of the contraption in action - you can see the stream of heather being flung out by the counter-rotating spreader shafts at the back of the hopper. The aerofoils above and to the side of the spreader shafts are to keep the whole thing stable as it's being flown under the helicopter.

Black Hill helicopter

And here's the net effect when you are stood underneath acting as a human marker flag. And yes it does itch when you get a load of heather down your neck, although the helmet and the goggles keep most of it off of your face :-) I was initially a little skeptical about the likely efficacy of this technique, but it was really very impressive. It gave a much more even coverage than hand spreading and is obviously far faster. The only problem was that the heather bags had been standing for some time, and the combination of them being stacked on top of each other, compressed, soaked in rain and then frozen meant that a lot of the brash was in solid lumps that jammed the spreader. However on subsequent days they got a machine up to re-shred the heather to get the lumps out and solved that problem.

As with the spreading done last year this is still very much an experimental technique, it will be interesting to see how effective it has been over the next couple of years.



Re: Airborne muckspreader

Looks pretty awesome - who is coughing up the dosh to do it? Is the transmitter closed down now? I remember going on a tour soon after it was built and marvelling that it rests on a huge ball bearing!

Re: Airborne muckspreader

The funding is coming from a variety of sources including the landowners, the full list can be found at http://moorsforthefuture.org.uk/mftf/main/Partners.htm. The transmitter is still going, although I think it only does radio transmissions now.

Re: Airborne muckspreader

Like the post, Alan. I picked up this entry as the first story on thepeakdistrict.net. Cheers!