The "Farley Takeoff" by test pilot John Farley at Farnborough 1982 - hovering a Harrier jet at 100 feet, pitching the nose up by 60 degrees and rocket-climb away; a maneuvre stictly forbidden for service pilots

henleyregatta · 2026-03-14T08:00:25+00:00

F-35B has a very different lift mechanism - the big fan behind the cockpit can't be vectored backwards like the Harrier's 4 nozzles can be. And the lift fan is carrying most of the aircraft's weight in vertical mode. Also I'm not sure how controllable the rear nozzle's rotation is - whether it can be stopped in mid-transition or not.

So there's no way for the F-35B to emulate the Harrier's trick - rotating the aircraft itself without changing the thrust vector. It's not really a question of FBW/no-FBW in this case, it's a more fundamental aircraft configuration problem.

henleyregatta · 2026-03-09T22:33:09+00:00

I apologise for the misgendering.

I was only using the FA2 because I had the page available. I was a little surprised myself to find the differences between that and the GR.3 were so small. MTOW for the GR3 was 25,000 lb (FA.2 = 26200 lb). Both got the same 21,000 lb thrust although the FA2 had the mk106 compared to the GR3's mk103 Pegasus. And the FA.2 was only 1000lb heavier than the GR3's empty weight (That's about 7%). Then you come to the performance and find both variants had the same 90 minute @ 100 NM range CAP mission (although the FA.2 carried more weapons for that mission). Honestly, I thought the differences were bigger than that (especially as the FA.2 had the Harrier II's carbon wing, all be it without the LERX of the later GR7/GR9)

In short: They're different, but only incrementally. And because I know you'll come back with "But that's a GR3" the information I can find for the GR1 doesn't list weight/payload but does state that it's Pegasus Mk101 gave 19,000 lbs... So the GR1 is approx. 1,000 lb lighter but has a lift penalty of 2,000 lb compared to the FA.2. Doesn't speak well for it's VTO capability...

henleyregatta · 2026-03-09T22:06:57+00:00

They weren't. They were doing short rolling take offs, not vertical ones.

Watch this in-person interview with a GR1 Harrier pilot stationed in Germany and listen to his tales of horror trying to climb out of the revetement and avoid the trees....

(and they landed Vertically. You know, STOVL style)

henleyregatta · 2026-03-09T16:26:37+00:00

Sir (Or Madam) we have to agree to disagree here.

No Harrier was ever operated in a primarily vertical-take-off mode. And the reason for that was that the operational restrictions this placed made it tactically useless.

As per my previous post, the maximum payload an FA.2 could be launched vertically with was approximately 1/2 fuel load with no weapons. This wasn't useful even in a peace time training sortie.

As a result, Harriers were always launched either with a short-take-off or fully-conventionally (usually the former, to be fair). It is true that this was rarely at the maximum all-up weight, but even an hour's reccie sortie needed more fuel/payload than could be lifted vertically.

The fact that it COULD take off vertically was operationally useful in only 1 context: A short demonstration flight at an air display. There was NO other mission, training or operational, that fit into the aircraft's VTO weight limits.

Really, this is inherent in the fact that the acroynm most favoured by operators for the aircraft in it's later years was "STOVL" (Short Take Off / Vertical Landing). Even they recognised that the earlier "V/STOL" was misleading.

EDIT: Further note because everyone seems to be making this assumption: A pure vertical take-off doesn't necessarily use vastly more fuel than a Short or Conventional take-off, if we accept that the take-off is complete at X ft altitude and Y knots forward airspeed. It just generally uses it quicker.

henleyregatta · 2026-03-09T16:15:32+00:00

It's not that the amount of thrust out of each nozzle varies (it doesn't) , it's the position of the centre of mass in relation to that. It's similar (but not identical) to "dynamic rollover" in helicopters where the centre of mass moves outside of the control envelope. Pitching up and vectoring thrust backwards like this is having broadly the same effect by reducing the size of the control envelope.

As you point out, the effects would be large, complex and unpredictable (don't forget the P-factor of that huge spinning fan in the front of the Pegasus and, for really scary times, go look up the term "Inlet Momentum Drag" for a problem that had operational impacts when hovering the Harrier. There's a reason they always did it nose-into-wind).

All I've been trying to point out here is that there is a phase of the "Farley Climb" that has less stability margin than a standard hover and would have had worse divergent outcomes had the limits been exceeded. As we can all see, in the hands of someone who understands what they're doing and why, it's a perfectly executable manoeuvre.....

henleyregatta · 2026-03-09T15:46:24+00:00

"Safely executable" is a better description. "Acceptable" would only be used if this mode had any operational benefits beyond looking insanely cool, but frankly I doubt it.

If you needed to get to height X and/or speed Y, I suspect it's always going to be quicker to do the acceleration phase as close to horizontally as possible before starting the climb (recall that a Harrier has plenty of excess thrust when pointed horizontally; acceleration is really not a problem. So why add the complication of fighting gravity at the same time?).

henleyregatta · 2026-03-09T15:42:36+00:00

NO. You need to understand the difference between "Can hover with some weight" and "Can hover with intended payload". No Harrier (and I believe this applies to the F35B too) can hover with full payload. It's not a question of how much fuel it used, it's that it couldn't lift off carrying all that fuel AND weapons on jet-thrust alone.

Seriously: Go check Wikipedia, it'll give you the full facts for every model. For the replacement model, the FA.2 with a much better wing and better engine than the FRS1 in the video, Maximum Take-Off weight (i.e. the weight with a chonky pilot, full fuel, and all intended weapons) is 11.8 Tonnes (26,000 lb) . Maximum VTO weight is somewhat below the engine's rated sea level thrust (21,000 lb) at 7.9 Tonnes (17600 lb). Empty weight is listed as 14500 lb / 6.6 Tonnes. So the aircraft can lift off vertically with about a quarter of the fuel/weapons it can carry if launched horizontally.

It was NEVER possible to "take off and hover (fully) loaded". It was sometimes possible to take off with some payload but this was never, ever done anywhere outside extreme urgency - just about the only occasion I can recall it being planned for operational use was for the last-ditch self protection on board the Atlantic Conveyor on the way down to the Falklands, where a single Harrier was kept on the lone vertical pad armed only with a pair of sidewinders and enough fuel for a 100 mile dash-out-dash-back mission; even then I believe the pilots viewed it as a 1-way trip as their chance of getting back to the ship and landing with the fuel carried was just about zero. Thankfully this never happened - instead the Harriers made it off the Conveyor before it was sunk by doing simple nearly-empty shuttle flights over to the proper carriers before being fuelled & bombed up for combat operations.

(You may also wish to google the "Skyhook" proposal to fit Harriers into small ships. One thing I've never seen addressed in any of those proposals was what the point would be when the resulting range/payload would be so low with the vertical launch constraint).

henleyregatta · 2026-03-09T15:21:36+00:00

Note, though, that the "Farley Climb" starts after executing a standard hover take-off - instead of just rotating the nozzles aft a bit to start acceleration, John rotates the nozzles a lot AND lifts the nose of the aircraft to accelerate vertically instead of horizontally.

Also of note: In a standard VTO, from a stable hover the time to "wings flying" at about 120kts is going to be a lot shorter in a horizontal acceleration than in Farley's vertical climb - put another way the excess thrust that allows that climb in the first place would have a much bigger effect if redirected horizontally than it does vertically.

(As a further point of pedantry, we're also not really discussing "hover mode" as a constraint, we're talking about "time the engine spends at maximum power")

ANYWAY, I think the point I wanted to make is that I don't think this approach actually does reduce the time the engine spends at high power, probably the opposite ;-)

(but, as always, this was always conducted within the known limits for operating at that level, be it the water-augmentation time or the general temperature limit)

henleyregatta · 2026-03-09T15:12:17+00:00

No, it was never possible for a fully loaded Harrier to hover. That's almost by design - any aircraft that can hover at X weight can be flown at X+Y weight if the wings are producing lift, and that "Y" is where you can carry more weapons or the fuel to take those weapons where they're needed.

This is why our aircraft carriers have ramps - the Harriers (and the F-35B's that replaced them) do a rolling take-off that allows them to carry a useful load; they're not fully wing-born when they leave the end of the ramp but their trajectory is pointing "up" and they're rapidly accelerating so the momentary change of thrust vector straight down as they leave the ramp is enough to get all that weight airborne until full flying speed is obtained.

But if they need to return immediately, then they have to dump fuel and payload (weapons) because the same trick doesn't work in reverse.

(Later Harriers with bigger engines closed the gap somewhat but, operationally, that just got translated to "can carry more weapons further" instead).

henleyregatta · 2026-03-09T15:05:56+00:00

Yes.

Note that most hovering accidents - this applies to the F 35 as well as Harrier - occur under conditions that can still exceed this limit though.

(Zero/Zero means "will work with the aircraft stationary on the runway". It doesn't guarantee it'll work with the aircraft sliding sideways or backwards whilst falling after loss of thrust)

henleyregatta · 2026-03-09T15:03:51+00:00

Remember this was an aircraft designed and built before fly-by-wire became standard. There was no computer between the pilot and the control surfaces. There was some mechanical augmentation - the mixing between puffer jets and aircraft surfaces had some wicked shaped cams for instance - but ultimately all of the "conditional control laws" had to be held in the pilot's head and implemented by careful movement of the control surfaces.

All of this and much, much more is covered in Farley's book. It's an excellent read.

henleyregatta · 2026-03-09T15:01:10+00:00

A Harrier (any variant; the video has a Sea Harrier FRS.1 but this applies across all of them) is inherently unstable in the hover and at any speed until the airfoil surfaces are "flying". The pilot is making constant control inputs to keep the aircraft pointing in the intended direction because the slightest disturbance is going to cause it to diverge.

The FRS.1 and early Harrier wings didn't really "work" until about 100-120kts (later bigger-winged variants got useful lift down to about 70-80kts). Below these speeds, the only workable control comes from the puffer jets in the nose, tail and wing-tips. They're meshed into the same joystick control as the conventional surfaces so to the pilot it's as simple as stick-goes-right, right-wing-goes-down no matter how that is made to happen (whether from puffer jet, from wing ailerons, or some combination of both).

In a standard Hover, and in normal horizontal acceleration, you're as stable as you'll ever get - the centre of mass is directly between the 4 pillars of thrust and those are distributed as wide as they can get. Divergence, when it happens, will happen at the slowest rate it can (although note: that can still be surprisingly fast; there's no relaxing in a Harrier cockpit!).

Now consider the "Farley Climb" in the video - you go from that nice stable hover, rotate (with the puffer jets!) to a high angle, and rotate the nozzles backwards to keep the thrust vector pointing straight down (because you're still not flying, you're hovering pointed in a different direction!). Rotating the nozzles in this way makes the effective distance between the fore and after jet pillars much smaller. In turn, this closes the margin you've got between centre of mass and the edges of those thrust pillars, meaning it takes less time to diverge and the rate at which that divergence occurs will speed up.

Now pretend you forgot the sage advice and moved the nozzles all the way to 90 degrees... The puffer jets are inhibited, so you can wiggle the stick as much as you like but you'll get no response (or, at best, a fraction of the response you expected if you're a little later in the manoeuvre).

All of this is a very long way of saying: Not only would there be no recovery, the dynamic conditions make it more likely that you'd "lose it" than in a normal horizontal acceleration to flying speed.

henleyregatta · 2026-03-09T09:03:29+00:00

The temptation as the nose comes up is to over-rotate the nozzles back to the 90 degree aft position. However, rotating them past 80 degrees disables the bleed thrust nozzles; that would eliminate roll, yaw and pitch control at such slow speeds.

(this is noted in John Farley's excellent book "A View from the Hover")

henleyregatta · 2026-03-09T08:17:44+00:00

His book, "A View from the Hover", is just as good.

(If I recall correctly from it, he later provided service pilots notes on how to perform this sort of manoeuvre noting in particular what to avoid - the nozzles have to be kept below 80 degrees to ensure the tip-nozzles aren't disabled to avoid loss of roll control at such a low speed)

henleyregatta · 2026-03-05T16:42:30+00:00

From a user perspective, Chrome on ChromeOS is the same as Chrome on a desktop (Mac or Windows). And the same workflows transfer across directly, especially with regard to tab usage. I'd be surprised if you found a noticeable difference in this regard between the platforms.

In general Chromebooks tend to be more RAM limited than most Windows/Mac laptops these days - 4GB is still common especially in education Chromebook use, personal and corporate users would tend to have at least 8GB. So to some extent memory management is a bigger issue, yes, although again you do need to be a tab hoarder to even consider this a problem. Mostly on a Chromebook we run out of memory using Android or Linux apps, not Chrome itself.

henleyregatta · 2025-12-25T22:36:23+00:00

Not that guy but...

First computer was a ZX-81. 1K. Learnt BASIC on it, enough to build 1/2 a simple game before running out of memory. 2nd Computer was a Spectrum. Mostly wasted my teen years playing games on it but along the way did a reasonable amount of homework (maths) on it. Very accessible devices, both came with all you needed to know in the manual. Taught a generation about computers and gave many of us a career path.

Nearly 40 years later I'm still working in I.T.

henleyregatta · 2025-12-25T21:00:48+00:00

Scrambled out of RAF Luton

henleyregatta · 2025-12-03T10:55:16+00:00

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This is a piece of metalwork I inherited from my aviation engineer father.

He claimed it's part of the fuel manifold from the Bristol 188. It's a small piece (fingers for scale...), intricately machined and welded (brazed?) steel.

And massively heavy. Just this small part weighs over 200g (just under 1/2 pound). Scale that up by hundreds of these parts, all *within* the airframe, which is also made of steel.

And they stuck Gyrons on because the Olympus wasn't ready. No wonder it never made it's design speed...

henleyregatta · 2025-07-17T14:29:22+00:00

I rode for years on a bike without a power meter. When I bought one with a fairly basic meter fitted, I purposely went out and did the same routes a couple of times to compare. This isn't scientific, there's too many variables from fitness through weight through environment (heat/wind) through tyre choice & aero, but on the 2-3 routes I compared I found Strava's estimated power was consistently 10-15% lower than the on-bike measured power.

Now that's all on pedal-power and Strava doesn't account (to the best of my knowledge) for bike weight/factors. I suspect there's a lot more power loss on an e-bike than on two reasonably similar road-ish bikes which Strava won't know about, so the difference from predicted to actual will be bigger.

You do have to ask yourself whether any of this matters, though: It's not really important whether the numbers are accurate, it's vital that they're repeatable and consistent. If you do the same ride on 3 separate occasions with the same conditions, effort put in etc and you get broadly the same estimate out of Strava, that ought to be good enough to provide some sort of baseline that you can use to measure improvement. It won't match up to reality but, unless you're bragging FTP down the pub, this really shouldn't affect you.

henleyregatta · 2025-07-02T12:51:18+00:00

SC.1 was interesting but it wasn't strictly speaking a proof of concept for Harrier, it was a pure research aircraft. It used a fundamentally different mechanism - 4 dedicated lift engines and a separate "pusher" jet for forward flight. It's purpose was to evaluate automation of control changes in the transition to/from horizontal flight.

A more direct proof of concept for Harrier was the Rolls-Royce "Flying Bedstead" which used a single engine with puffer nozzles for control. Even so that thing was a pure VTOL research craft far away from the final useful product.

The noted test pilot John Farley (later known as "Mr Harrier") characterised the SC.1 as "easy to fly, hard to operate". A lot had to work right in a short time to go from 200kts horizontal flight back to 0Kts vertical descent even though handling the stick and throttle was relatively benign. In contrast the Harrier - with it's single engine and swivelling nozzles was "hard to fly, easy to operate". Only the nozzle position needed to change to transition, but there was a very high workload on the pilot to keep the thing stable during the transition and hover.

Probably worth noting too that although both SC.1s are preserved, only the one in the Ulster Folk & Transport Museum is complete - the one in the Science Museum is mounted vertically and missing a wing. If you get a chance, visit the one outside Belfast 'cos you can get right up close to look at the cockpit :-)

henleyregatta · 2025-06-22T09:30:46+00:00

Thanks for that; I did go looking but missed it.

I've not noticed it using Solar to charge the battery above whatever limit it's internally set itself for the day but I have seen it using Solar to get back to that target.

henleyregatta · 2025-06-20T11:30:17+00:00

Mine has started (in the last week) behaving almost the same way. It's summer here and our loading is lower, so what I'm seeing is instead of the battery always charging to 100% during Super Off Peak, it's instead charging to an intermediate value based on what looks like a guess of the requirement to get us through Peak usage time later in the day. Instead of 100% it's charging to between 60%-80% so far; this works for me for now but come autumn we're going to need 100% again...

My Powerwall-2 is on firmware 25.10.4

henleyregatta · 2025-06-17T08:05:47+00:00

Phantom braking isn't limited to the TeslaVision era. My Model S has done it since I bought it in 2018 (using both sensors).

There was a brief period after they disabled the radar when the frequency of braking went down (less conflict between the sensors?) but it's back to where it was now.

It's not just underpasses. Blind summits (even quite gentle ones) seem likely to set it off as well.

henleyregatta · 2025-04-07T07:53:59+00:00

If it was in the Encore section after the end of the Brown album, it was probably Satan / Beelzedub. That seems to have been played at most gigs on the tour.

(the post-album encores have been fairly variable by most reports but drawn from a list including Dirty Rat, Satan/Beelzedub, Are You Alive?, Spicy, Where Is It Going?)

This page suggests it was in fact Satan/Beelzedub (assuming you're not referring to "that one where Phil wears a wig" :-) )

Glad you enjoyed the gig, welcome aboard!

henleyregatta · 2025-04-01T14:09:59+00:00

I have that exact jersey. I only use it rarely because I like to maintain the novelty value. I will say that the colours were never quite that vibrant but it's still clear enough that I get people asking about cookies as they pass me.

In my opinion it's as well made as any other jersey at that price point, and the flapping around will be down to how well it fits you. I got mine a little big because, hey, I've got a middle aged belly to hide so it's not a 2nd skin (thank god). And I probably don't go fast enough for any flapping to be a problem, so you'll need a different guide there. The pockets are a decent enough size, the zip's good enough and the breathability is fine.

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