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Comment by Mikeb85 | Hacker News Reader

As interesting as the Avro Arrow was, it's capabilities have been exaggerated, and there were a decent number of Mach 2 capable jets of the same era. More interesting is the downfall of Avro and the effect it had on Canada's engineers and brain drain...

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The Convair F-106 Delta Dart from the same era was likely faster (Mach 2.3 vs. Arrow's fastest test at Mach 2). And the Delta Dart was no great interceptor, they only built a few hundred. This was the era where Air Power doctrine had to painfully accept that high speed high altitude was becoming too vulnerable to SAMs.

The fastest war plane of the era was the North American Aviation XB-70 Valkyrie, which was an enormous bomber which cruised at Mach 3+ and 70,000 feet for nearly 4,000 miles. Neither the Arrow or Dagger could touch it, but SAMs could so it was canceled after a very successful test flight program.

The world changed to low altitude penetration, a role which would have cut the B70s range substantially because it's design actually far more efficient at Mach 3/70,000 feet than it was at Mach 0.95 at 1,000 feet.

Speaking of Convair, It's always a shame to read about all these companies from they heyday of aviation - so many companies making so many planes. I went to the Aviation museum in Ottawa and looked at all the forgotten names...

Canada used to have multiple brands of aircraft manufactures, making multiple combat planes. The USA had a plethora of manufactures I can't even keep track of them all.

Now? We have just Bombardier, who makes solid passenger craft and fails to make large jetliners and LRVs.

I would disagree that the F-106 wasn't a great interceptor as it apparently was (and was a pleasure to fly).

The issue is that by the time it made it to production, the major threat had become the ICBM rather than the bomber. USAF Air Defense Command in general was defunded but ABM never took its place.

Well my greater point was that high speed high altitude intercepters were becoming obsolete while the Arrow was being built. As much a pleasure as the Delta Dart may have been to fly, it wasn't produced in great numbers because it wasn't designed for the new threats.

Sure, but the performance envelope on the Arrow was not even close to being tested - it was cancelled before it was fitted with the engines it was actually designed to use. Some of the maximum performance numbers are overstated for sure, but it's hard to say what it's real performance would have been. Similar things can be said for the range - the final numbers for that _should_ have been much higher.

Also keep in mind, this was designed as an interceptor for defence of the vastness of Canada against Russian long-range bombers. It wasn't just about speed, but the combination of speed, range, and advanced avionics that made the Arrow important.

I don't know why you'd compare this to the XB-70, they're vastly different designs for different purposes.

When Sputnik and the threat of ICBMs loomed, most assumed interceptors were a waste of time - which turned out to be a premature assumption.

All in all, it was probably the right decision to cancel the program, as it's costs has spiralled out of control - but to make direct comparisons of production aircraft to prototypes seems unfair.

I wouldn't hold up any Century Series aircraft as an example of anything other than extravagant expenditure. They were all garbage when compared against the actual missions they needed to perform. That was mostly the result of brain dead acquisitions on the part of the DoD.

Be careful with the "top" speeds of military jets. The F-16 claims mach 2+ but it cannot do this with any realistic combat load or mission profile. The vast majority of its time will be spent subsonic, with mere seconds at mach 1.6 to release weapons.

But specs are deliberately under quoted I recall a former co worker who had worked at RAE saying that whilst on the range at salisbury plain was over taken by a the then standard MBT in a land rover doing 50 he reckoned it was doing 65-70 well over the MBT's quoted top speed.

The F-16 values are from actual aircraft operations. I don't know what an MBT is or how it relates to aircraft.

MBT usually means Main Battle Tank.

I agree, I have no idea how it relates. Plenty of MBT's have very high top speeds under ideal conditions. The actual top speed is usually to something lower to prevent damage to the tanks tracks however.

And the SR72 / backbirds top speed is still classified to this day - I suspect that at WEP (war emergency power) a f16 is faster than quoted

I believe you meant to say the "SR-71".

A SR71 would not have "War Emergency Power". I'm not even sure I've seen reference to "War Emergency Power" on any turbine engine. It's simply not a combat aircraft. As a matter of its regular operation, it must be capable of outflying any aircraft or missile in pursuit. In other words, flying at the absolute maximum airspeed was a normal event that is a possibility in every mission. Not a last ditch effort to disengage.

You really have nothing to back up the claims you are making. Not only is the SR71 no longer in operation, the aircraft don't even really exist anymore. The static displays out there largely had their wings cut off for transport. They were just reattached on site afterwards. They aren't airworthy any longer. Even if the top speed was a bit higher than published, there would be no reason to keep it classified now.

Plenty of pilots have published memoirs about how regular flight was Mach 3, with excursions to Mach 3.2. The absolute speed is just like any other aircraft. It's limited by design factors. Of course some crews wound up flying faster than Mach 3.2. But it's not like the blackbird was running around secretly at mach 10 or something.

I think he's referring to the fact that you can get higher than "normal" speed if you dump your weapons and accept damage from the heat, either air friction heating the skin of your plane, or just your engine temperatures. You may be able to maintain it for a short time to evade something.

Its similar to the way you can get your car to exceed design parameters if you risk blowing the engine and disable the speed limiter.

Anything can exceed its design speed if you override or ignore the design guideline.

I am sure the F-16 may well be faster than the number I gave, but an F-16 has like 20 minutes fuel, maximum, on afterburner. Add in flight time to target, and drag from weapons, and the time taken to accelerate, and you see why they can't do it except on test flights.

I do not think you can find any documented instance of a Viper exceeding mach 1.8 in combat. F-18s recently intercepted a "suspect" airliner at mach 1.6.

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