...go supersonic in a vertical climb?
Obviously this isn't 'level flight' and I'm pretty sure that a Lightning doing 'Mach 2' can pull-up and still be doing over 'Mach 1' when it reaches the vertical (if the wings don't come off in the process) but can a Lightning already going vertical at less than 'Mach 1' (and I appreciate that this will be changing rapidly) break the 'sound-barrier'?
(P.S: Mine's a pint of cider.)
Last edited by Creaking Door; 17th April 2017 at 14:20.
I really hate long winded answers can you not just get straight to the point Sabrejet
Apologies: no it can't.
But still deeply impressive to witness.
According to one of my old mates who was a Wattisham intercept jockey; from a roller on the O/R pad; at unstick, they would lower the nose for rapid acceleration to 430 KIAS before initiating a climb, stabilizing at 450 KIAS. Around 13,000 ft the “Lightning” would reach Mach 0.87 and maintain this speed until reaching the subsonic service ceiling of the tropopause at 36,000 ft. on a standard day.
He said they could generally achieve this attitude in under three minutes.
If climbing further, pilots would accelerate to supersonic speed at the tropopause before resuming the climb. on full re-heat topping out at about 65,000 feet on a good day. There are records of Lightning trials doing dummy intercepts of Upper Heyford Lockheed U2s in excess of 65.000 feet.
Then promptly having to refuel
Actually, having checked some figures, I realise what an impossibility this would be:
EE Lightning, depending on mark, had about 16,000lb from each Avon engine on full afterburner, against an empty weight plus 1000lb of fuel of over 32,000lb...
...so, no, it could just about hold its vertical speed under those (unlikely) conditions! And then crash, fuel gone.
How did that performance measure up against its foreign rivals ?
Amazingly; it could run-out of fuel faster than anything on the planet!
And a set of mainwheel tyres per landing, given a mild crosswind.
Sorry, you'll have to expand on that a bit for me; jet engines / jet aircraft aren't really my thing.
Mass-air-flow I understand (I think) but what on the engines was 'trimmed'? (up to 'Mach number 1.4'(?))
I spoke to a chap once about the Blue Streak ICBM and the engines on that were 'trimmed' (the thrust was adjusted) by putting an orifice in the fuel delivery pipes. Before that I had no idea that rocket engines were, or even could be, run more than when they were launched!
Last edited by Creaking Door; 17th April 2017 at 22:08.
Because the engines had been upgraded with a higher mass flow, the intake couldn't allow enough air into the engines in a static state. They therefore limited the engine speed and full reheat until it reached Mn 1.4.
As I pointed out, the mass air flow sea-level static state (SLS) was 150lbs per second through the 200's and 170lbs per second through the 300's. That was of course, data measured on the thrust rigs at RR.
Surely a more appropriate question would be "Could the EE Lightning..." given that none fly.
XS422 is on the way?
That was British fuel efficiency, they realised the damned things leaked fuel so badly, it made sense to try and burn it as quickly as possible, thus not wasting fuel.Amazingly; it could run-out of fuel faster than anything on the planet!
Did the Lightning get any official records at all?
A few points from Wiki (sorry):
The Lightning’s optimum climb profile required the use of afterburners during takeoff. Immediately after takeoff, the nose would be lowered for rapid acceleration to 430 knots (800 km/h) IAS before initiating a climb, stabilising at 450 knots (830 km/h). This would yield a constant climb rate of approximately 20,000 ft/min (100 m/s).[nb 3] Around 13,000 ft (4,000 m) the Lightning would reach Mach 0.87 (1,009 km/h) and maintain this speed until reaching the tropopause, 36,000 ft (11,000 m) on a standard day.[nb 4] If climbing further, pilots would accelerate to supersonic speed at the tropopause before resuming the climb.
The official ceiling of the Lightning was kept secret; low security RAF documents would often state in excess of 60,000 ft (18,000 m). In September 1962, Fighter Command organised interception trials on Lockheed U-2As at heights of around 60,000–65,000 ft (18,000–20,000 m), which were temporarily based at RAF Upper Heyford to monitor Soviet nuclear tests.
In 1984, during a NATO exercise, Flt Lt Mike Hale intercepted a U-2 at a height which they had previously considered safe (thought to be 66,000 feet (20,000 m)). Records show that Hale also climbed to 88,000 ft (27,000 m) in his Lightning F.3 XR749. This was not sustained level flight but a ballistic climb, in which the pilot takes the aircraft to top speed and then puts the aircraft into a climb, exchanging speed for altitude.
If you're not living on the edge then you're taking up too much space!
Think Delusional is a bit harsh !
Yes a lot did crash and yes they had a very short range, but as a display aircraft they were impressive.
I think anyone who saw the two lightnings depart Mildenhall air fete in 1988 , especially knowing they'd never see it again , could not fail to be impressed.
How many crashed out of how many built?
As we are talking supersonic aircraft, to add a theoretical fly in the ointment,
could Concorde achieve supersonic flight in the vertical?
Empty and with full power?
There are currently 1 users browsing this thread. (0 members and 1 guests)