Anyone Flown The Mach Loop ?
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From: MAN. UK.
It's in Class G airspace without a training area or any other restriction around it so by law it's a free piece of airspace that you can enjoy at your will.
As to what height you want to operate is another matter and anything below 500' from any person, vessel, vehicle or structure will be by exemption from the CAA. I believe there are some civilian military jet/warbird operators who do have such clearance. The military operate to 250'.
As for timing, whilst it's not 'restricted', the threat and error management arguments for toddling around it in a Cessna 150 whilst risking a fast jet enema are such that a weekday flight is not advisable. I know several operators who regularly use it on weekends though.
To be honest, being based at Hawarden I can tell you that there are far more interesting areas of North Wales that offer better low level scenery (without photographers too!).
As to what height you want to operate is another matter and anything below 500' from any person, vessel, vehicle or structure will be by exemption from the CAA. I believe there are some civilian military jet/warbird operators who do have such clearance. The military operate to 250'.
As for timing, whilst it's not 'restricted', the threat and error management arguments for toddling around it in a Cessna 150 whilst risking a fast jet enema are such that a weekday flight is not advisable. I know several operators who regularly use it on weekends though.
To be honest, being based at Hawarden I can tell you that there are far more interesting areas of North Wales that offer better low level scenery (without photographers too!).
Joined: Mar 2006
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From: UK
Many times, in Lightnings and Tornados before it became known as the Mach Loop, but as this is The Private Flying thread, I guess you’re not interested in what happened 40+ years ago when we actually had an Air Force.
In those days we’d go both ways and if anything, going the opposite way to what is now the norm was far more exciting. You could get really low in the valley, way below road level and as you crested the ridge at the top, you rolled almost inverted and pulled down to follow the lead in road.
Even then there were a few private flyers that thought they could get away with flying really low over a lake or down a valley. 4 of us encountered one such guy doing a bit of illegal low flying over a lake, perhaps showing off to his girlfriend? Anyway 2 of us went down one side, 2 down the other at around 480kts, close enough to make the point that he shouldn’t be there and I’ve never seen a C172 climb so fast.
In those days we’d go both ways and if anything, going the opposite way to what is now the norm was far more exciting. You could get really low in the valley, way below road level and as you crested the ridge at the top, you rolled almost inverted and pulled down to follow the lead in road.
Even then there were a few private flyers that thought they could get away with flying really low over a lake or down a valley. 4 of us encountered one such guy doing a bit of illegal low flying over a lake, perhaps showing off to his girlfriend? Anyway 2 of us went down one side, 2 down the other at around 480kts, close enough to make the point that he shouldn’t be there and I’ve never seen a C172 climb so fast.
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From: UK
Even then there were a few private flyers that thought they could get away with flying really low over a lake or down a valley. 4 of us encountered one such guy doing a bit of illegal low flying over a lake, perhaps showing off to his girlfriend? Anyway 2 of us went down one side, 2 down the other at around 480kts, close enough to make the point that he shouldn’t be there and I’ve never seen a C172 climb so fast.
G
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From: Too close to Croydon for comfort
If I recall aright, Red Bull took their DC-6 through the Mach Loop a year or two back. Naturally, when I was there in the Tal-y-lynn valley with my Australian cousins a few years ago nothing used it...
Edit:
Edit:
Last edited by treadigraph; 12th December 2025 at 15:13.
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From: Nanaimo (CAC8)
I would prefer to fly the A5 route over Llyn Ogwen and the Nant Ffrancon valley. I saw many Gnats doing this in my youth:
The floor of the Nant Ffrancon is 300' lower than Llyn Ogwen, so a partially-inverted turn and pull is required.
Looking up the Nant Ffrancon:
The floor of the Nant Ffrancon is 300' lower than Llyn Ogwen, so a partially-inverted turn and pull is required.
Looking up the Nant Ffrancon:
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From: DM33
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From: MAN. UK.
Just Google 'The Mach Loop' and there are several sites offering details. This one is representative;
The Mach Loop.
The Mach Loop.
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From: MAN. UK.
It's a good job the jets coming the other way would be lower than you!
Joined: Nov 2018
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From: UK
It's always a must when the winds aren't too high, else it gets a bit bumpy and unpleasant. Usually I do the second half of the loop going backwards, so I descend down the valley towards the sea and then head along the coast low level to wherever I'm going. Sadly since Llanbedr is all but closed, there's only Caernarfon to visit.
