Mach Loop
- Les Pickstock
- 6 days ago
- 5 min read
The Mach Loop, more correctly known as the ‘Machynlleth Loop’, is a series of valleys in west-central Wales used for low-level flight training by military aircraft. It's located between Dolgellau and Machynlleth (from which it gets its name – it is not related to the speed of sound), and is part of the Low Flying Area 7 (LFA7). Post Code: LL40 2SG. The challenging terrain and unpredictable weather conditions make it an ideal location for pilots to practice low-level flying, with aircraft sometimes flying as low as 75 meters above the valley floor.
At airshows, as exciting as they can be, most imagery is captured from below – the underside of the planes - unless a pilot pivots his aircraft to show the topside (and occasionally waves). This is can be dangerous as it loses energy, potentially then height, for a craft already flying low to give the crowds a good view. The Mach Loop offers the potential to photograph the planes from above or side, and without a bright (burnt out) sky as background.
There are numerous locations to take photographs, though most require arduous climbs to reach the vantage points. The most popular (and best) are Cad West and Cad East. Dave Newby and I had both been up Cad West a number of times (the most arduous to climb) so decided to go to Cad East, driving up a farmer’s track (semi officially open to the public as long as you shut the gates, leave no litter and do not stay overnight). This removes 90% of the climb, leaving only a 15-minute walk, after parking, to get to the first viewing ‘shelf’. I stopped there, but Dave wished to go right to the top – the third shelf (at 462m up).
The track is rather treacherous, only one car (tractor) width with no passing places and the huge hill to the right and a calamitous drop to the left. At the top there is only room for 3-4 cars so early arrival is key. We arrived at 06:45 to find only one space available.
Unfortunately there was heavy mist along the valleys and we were concerned this would disrupt flight plans – and it did. Aircraft will not fly in poor visibility, strong rain, snow, mist/fog etc. Whilst still some high level mist, about 09:45 two brave USAF F35As came unexpectantly shooting through.
Fast jets, through the loop, are travelling at over 400MPH so you have but a few seconds to focus and track the planes from first hearing them. Usually there are other friendly photographers with radio ‘scanners’ who shout “incoming!” before the planes come into sight, giving you an extra 5 seconds or so to ‘get ready’.
About 11:00am two RAF Texans (prop trainers) came through; rather slower than the ‘fast jets’ so theoretically easier to capture. But being far less noisy than the jets, they are on you before you hear them. Again, other photogs with scanners usually give you a helpful warning.
These were followed by two different helicopters at 12:00. Unusually these flew ‘across’ the valley, rather than through it. One was an air ambulance; the other just looked like a ‘normal’ civilian chopper, with no military etc markings.
Air traffic then seemed to increase as two RAF Hawks then flashed through by 12:15, unfortunately turning their topside to Cad West.
With no further activity after the Hawks, Dave and I decided to pack up at 16:10, when the guys with the radios warned of an incoming F35. Nothing appeared, though, and they called ‘false alarm’ after 10 minutes. Dave set off down to the car when two Texans suddenly appeared, without warning. So he missed them!
Rather disappointingly, we only saw these 8 planes (4 pairs) and two slow helicopters on this trip. The afternoon especially was somewhat boring as there was a 4 hour gap between flights.
The aircraft do not fly through the loop at weekends or bank holidays. Further, there is no practical ‘schedule’. It is ‘luck’ if any fly past at all whilst you are there. And what type of aircraft is also un-predictable, though there are mostly American ones these days.
For ‘fast jets’ Cad West remains the better choice: part of the training requires flying ‘sideways’ along the valley. Quite a difficult manoeuvre as balancing no lift, engine power and directional controls is not easy – thence ‘training’. As most photographers are on the Cad West side, the pilots usually flip so their topside shows to them. Thus, often from Cad East you only get to see the underside of the aircraft. This is not an issue for larger aircraft, Osprey helicopters etc.
PHOTOGRAPHY
As the planes are relatively close (and noisy!) you do not need super-long lenses. 200-300mm are wholly adequate. During this experience I shot most images at 200mm. More important is patience, fast focussing, focus retention and high frames per second. When the planes are against the sky, you need to add up to two stops of extra exposure. When against the mountain backdrop, no exposure variation is required. However as you only have (maybe) 2-3 seconds to complete the whole fly past changing exposure is impractical. Regular photographers choose to alter their exposures for different flypast events, rather than trying to correct during a single pass.
Shutter speed is another important variable. With propellor planes, such as the RAF Texan, speeds less than 1/500S are required or the propellors will be sharp, appearing stationery. However care needs to be taken to avoid camera shake at these speeds with a long lens.
These are also ‘good’ speeds to pan fast jets, to blur the background, but keeping the plane relatively sharp, and indicating ‘speed’. To achieve maximum sharpness though requires shutter speeds in excess of 1/1600S.
Humping a number of cameras and lenses up the steep hills is not recommended: one camera, one zoom lens is. You are likely to take hundreds of images, so spare cards and charged batteries are a must.
WEATHER and REFRESHMENTS
The Mach Loop is in the Welsh mountains; assume any visit can have really bad weather. Hot drinks and energy food are advised. Also seating. Standing at the top of a windy mountain for 8-10 hours is boringly tiring whilst awaiting 5 seconds of a flypast. Whilst adding to the weight to hawk up the mountain, some kind of chair is strongly recommended. There are NO toilet facilities or ‘private’ bushes!
Cold/windy/wet weather clothing is a ‘must’ – layers can always be taken off. Good climbing or walking boots are also necessary. Regular visitors often take 1-2 man survival tents ‘just in case’ or to rest whilst awaiting the next arrivals. Surprisingly ‘UV burn’ can be aggressive, so high up, even in non-sunny weather.
If not seen before, I suggest you view this video (as well as others on YouTube):
Can't wait to go back again, Great blog.🙌
Excellent blog, Explaining how the Mac loop came about, and how fellow photographers, wishing to go there what to expect, I would personally recommend as difficult as it is every photographer to have a go, but be aware once you've done it once I'm sure you'll be back again, very well written Les.👍