why don't we already have supersonic business jets (SSJBJ)?

[Johnny_L.A]

@Habeed

One major issue is that it isn’t legal to travel faster than the speed of sound in many, many places. (because the sonic boom causes disturbances and can even break windows)

This. You can buy a supersonic jet for $70,000, but your options for flying supersonically are limited.

@Habeed

if you have to spread those costs between a few aircraft purchased by wealthy patrons, the per aircraft cost could exceed what even billionaires are willing to pay.

I’ve been ranting about this for years. The cost of a Cessna Skyhawk has risen to the point where most people who can afford to buy one are buying more capable aircraft than Cessna Skyhawks. (Or they’re just using the corporate jet.)

@Francis_Vaughan

Given that of 1148 T-38s built…

But the mega rich are more likely to want to fly in ultra luxury with all their staff than ride in a cramped death machine.

Last time I checked, you could get a T-38 Talon for about $2 million. If I had the money, not only to buy one but to operate one, I’d totally do it. I’d rather have fun than luxury.

@coremelt

Ok, so just how bad is the sonic boom? can’t it be mitigated by climbing to 10km high before you go supersonic?

I used to work at Edwards AFB. Sonic booms were relatively frequent. I remember the Air Force 50th anniversary air show when Chuck Yeager went supersonic in an F-15 at 50,000 feet. It was still pretty loud on the ground. I don’t recall how high the Space Shuttles were when we heard their distinctive double booms.

[Duckster]

The Federal Aviation Administration has recently issued a new sonic boom regulation which bans nearly all supersonic flight by civil aircraft over the United States and its territorial waters. The regulation, which became effective April 27, 1973, prohibits the operation of civilian aircraft at speeds greater than March [sic] 1 without authorization from the agency. The policy underlying this regulation puts the burden of establishing the environmental acceptability of supersonic civil aircraft flight on the proponent, rather than on the affected public. However, the FAA has also made available reasonable opportunity for aircraft manufacturers to prove the environmental acceptability of supersonic flight if they are able to control sonic boom research without harmful effects on the public.

(Bolding mine.) (January 1973) http://elr.info/news-analysis/3/10067/faa-promulgates-strict-new-sonic-boom-regulation

[Kent_Clark]

According to NASA, supersonic aircraft typically fly at altitudes above 48,000 feet and produce sonic booms that are noticeable on the ground.

[md2000]

@clairobscur

During my childhood, the very rural area where I lived was oferflown by fighters on a regular basis (I’d guess we had a sonic boom once a week or so). It’s not that bad (not as violent as an explosion, for instance), but it’s enough to make windows vibrate, for instance.

I always had believed that we were on some flying path between point A and point B. I sort of assumed that military crafts were flying supersonic all the time, and until I read this thread, I never paid attention to the fact that I never heard a sonic boom anywhere else.

So, I gather from this thread that fighters were probably flying at supersonic speed specifically in this area because it was mostly uninhabited.

We had what we thought was a sonic boom in downtown Toronto when I was in grade 3; basically, think of the loudest commercial fireworks boom you’ve heard… Did not hear about damages.

Never heard one again, I assume whoever did it got a talking-to from his commander, the mayor, the premier of Ontario, and the Canadian high command…

Think of the energy required to produce a giant boom miles away, continuously through the flight. Where SST would be good would be across the Pacific, changing a 10-hour flight to a 4 hour flight; but IIRC the Concorde barely made it across the Atlantic. Having to put down in Hawaii to refuel, and then again in Vanatu or Manila, would negate the benefit of a fast flight.

[swampspruce]

Why bother when you can fly a G650 at near mach which FAIAP is close enough? It is also a bargain at a mere $65 million and change.

[Slash1972]

@Johnny_L.A

This. You can buy a supersonic jet for $70,000, but your options for flying supersonically are limited.

Sorry to derail, but is this link for real? You can buy a Mach 2 fighter jet for $70,000? and fly it?

[GusNSpot]

@Slash1972

Sorry to derail, but is this link for real? You can buy a Mach 2 fighter jet for $70,000? and fly it?

You can even fly it under the speed of sound with a lot less fuel burn and still do all that nifty acrobatic and dog fight stuff. Get a buddy to get one or a 100 Sabre and you can really have some fun.

Of course you can’t strut your stuff at the little local airport either.

:rolleyes:

[Broomstick]

Well… probably.

I mean you can fly it… after you get your license… and the appropriate sign-offs for high performance, jets, etc… but cost per hour and insurance is really going to take a bite out of your budget.

Sometimes the big cost isn’t in buying the airplane, it’s maintaining it and paying for stuff like fuel.

[Slash1972]

@Broomstick

Well… probably.

I mean you can fly it… after you get your license… and the appropriate sign-offs for high performance, jets, etc… but cost per hour and insurance is really going to take a bite out of your budget.

Sometimes the big cost isn’t in buying the airplane, it’s maintaining it and paying for stuff like fuel.

Oh yeah, I get that. But for 70K, it would almost be worth it to forgo licensing, insurance, and maintenance, and take it out over the desert in Nevada or something, hit Mach 2, and then eject (preferably NOT at Mach 2), and walk away abandoning the wreckage.

(this assumes no one on the ground gets hurt)

[Johnny_L.A]

@Slash1972

Sorry to derail, but is this link for real? You can buy a Mach 2 fighter jet for $70,000? and fly it?

Yes. Though U.S. models are more expensive. Not being in the market, I don’t know everything about it. You will need to have a type certificate for the specific type of aircraft. (This applies to turbine-powered civil airplanes too.) I believe turbine-powered ex-military airplanes need to have a formal maintenance plan. They’re probably going to be registered in the Experimental category, or possibly the Restricted category. And of course, you’ll have little opportunity to exceed Mach 1.

Seventy kilobucks may sound cheap; and it is. But that’s just for the airplane. These things consume kerosene like a Southerner guzzles sweet tea. Aircraft maintenance for your typical Bugsmasher 150 is expensive enough. The costs are enormous for jets – especially ‘special purpose’ ones. And if you want or need a spare engine, that can get ‘spendy’. Oh, and that type certificate. I think you need a certain number of hours before you can apply for one. (I’m not sure about that; I think I read it somewhere.) Many of those hours will be in higher-performance airplanes that can cost hundreds of dollars per hour. Some or many of those hours will likely be in jets – possibly something like a T-33 or even a T-38. Those will be a bit more expensive. You’ll need to find an instructor who can teach you how to fly the thing. If you need, say 1,000 hours to start training in your $70,000 MiG, it’s going to add up. (But of course, if you have the ducats to consider your own ‘fast-mover’, you’re probably not too concerned about costs.)

But yeah, you can buy a supersonic ex-Soviet Bloc airplane for under $100,000. As I said, a T-38 will probably cost around $2 million to $2.5 million, and an F-104 will probably cost a little more than that.

[Johnny_L.A]

@GusNSpot

Get a buddy to get one or a 100 Sabre and you can really have some fun.

There’s an F-86 Sabre for $275,000… but it’s a project. (There are also a couple of F-86s listed under Canadair.)

@Slash1972

Oh yeah, I get that. But for 70K, it would almost be worth it to forgo licensing, insurance, and maintenance, and take it out over the desert in Nevada or something, hit Mach 2, and then eject (preferably NOT at Mach 2), and walk away abandoning the wreckage.

(this assumes no one on the ground gets hurt)

Um…

[Diceman]

@Jinx

The real tragedy is that tragic accident that killed SST, a tire blow-out, was NOT directly caused by tire failure! The investigation concluded there was debris on the runway that induced tire failure (as opposed to the worrisome build-up of heat on the tires known to cause blow-outs). SST was coolest thing when I was a kid…pre-dating the Space Shuttle.

As I remember it, there were strong suspicions in the aviation community that the Concorde was not profitable to operate, but it was too much of a prestige craft to just scrap them. If this is true, then the accident was most likely siezed on as an excuse to retire the Concorde, with the specifics of the accident’s cause not really entering into the decision.

As others have mentioned, there is much less demand for SST these days. In 2015, if you want to talk to people in Toyko, you don’t hop on a jet, you Skype.

[usedtobe]

See BD10J - a trans-sonic “Kit” airplane.

(I actually saw a streak of the prototype at Mojave).

I was also raised a few miles from Wright-Patterson AFB (Dayton OH) in the 50’s.
Sonic booms were routine - until the Air Force got tired of buying windows.

The discussion of the BD10J was that the rule was NOT “No sonic Booms” but “No Sonic Booms Which Reach the Surface” - with the critical altitude being FL400 (40,000’ MSL).

So, if you wanted to fly straight up and then level off at FL410, you could push the throttle all the way forward and make your own little boom.

Of course, that would exhaust your fuel.

I know of 2 of them being built - both by people who were intending to set up shop to build them for others. One outflanked the other and bought, not only a kit, but exclusive rights to the design, all engineering data, etc.
He thought he could improve the tail design.
His left elevator disintegrated at 300 kts. Never got close to a boom.

The FAA breathed a huge sigh of relief - how do you regulate a bunch of cowboys in their toys making messes?

[Richard_Pearse]

@Slash1972

Sorry to derail, but is this link for real? You can buy a Mach 2 fighter jet for $70,000? and fly it?

Yeah, Migs are cheap. A friend of mine used to have a Mig-15 (not supersonic but still quite cool), the problem was it was uninsured because the insurance cost was going to be 20% of its value per year, and he wasn’t game to fly it. Another guy flew it, ex RNZAF Skyhawk pilot. They operated out of a short runway and the approach and landing always looked pretty hairy, requiring several approaches before he was happy to touchdown.

If you want a jet you’re better off getting something like an L39 Albatross. No it’s not supersonic but as mentioned above you can’t actually fly supersonic in very many places. What it is is docile and simple to fly while still having modern looks and, I’m told by an ex F-4 pilot, it gives a decent kick in the backside when you apply power for take-off. It is also cheaper than a Cessna 172.

[Hail_Ants]

Simple answer is: In order for the Concorde to go twice as fast as regular airliners it had to cost between 10 & 20 times as much. Both to build and to operate. This is why Boeing abandoned it’s SST project early on (and why the Concorde group should have as well). It’s a classic diminishing return that is obviously economically unworkable.

The only reason the Concorde did get built and operated amounted to little more than national prestige (and the fact that it didn’t lose *too *much money, thought it *always *lost some). As far as some billionaire wanting that, well, billionaires are very smart people who generally don’t make such obviously bad economic decisions, ego or not…

[coremelt]

@Hail_Ants

Simple answer is: In order for the Concorde to go twice as fast as regular airliners it had to cost between 10 & 20 times as much.

I would like to see some cites for that. Really that much more than a 747 per passenger mile?

And is it also still true with modern composite materials and better airflow modelling and engine designs?

[Francis_Vaughan]

The price of the MIG reminds me of high performance sailboats. They cost many millions, cost millions a year to campaign, and will turn up for sale at what amounts to zero money. The problem is that they will cost you at least a few million to get back into race winning shape, and will cost you a couple of million a year to continue to campaign them. A recent example being Lahana, now Rio 100.

The entire development costs of Concorde were essentially written off by the British and French governments. So their airlines got the planes for close to free. The maintenance costs were horrendous. The planes were constantly X-Rayed looking for issues, and they spent an inordinate amount of time in the hangar, and not flying. On just about every metric they were a commercial failure.

If you want to see what the difference modern design, engines and composites mean to aircraft design - compare a 767 to a 787. That is a good approximation to the performance gains over the Concorde you might hope for.

[Magiver]

@DinoR

They don’t (cite).

The link talks about an issue with US aircraft over Wales. At 18k the sonic boom caused some ceiling tiles to fall. Not cataclysmic but not the kind of shake I’d want over anyplace I lived. It also covers the rules in the US which includes limited places allowing supersonic flight. FAA allows supersonic flight over 60k feet though anywhere. Throw a ceiling of over 60k feet on to the design specifications for any plane that wants to regularly use it’s supersonic capability.

4 jets did it in my area during 9/11. No damage AFAIK. Not something you want to wake up to at 4am.

They would have been F-16’s.

[usedtobe]

The problem is, at supersonic speeds, air starts to act more like water.

Aluminum is cheap; but making an “SS-anything” out of aluminum would require the parts to be so massive that it would take REALLY prohibitively expensive power to even make it fly at all.

So, aluminum is replaced with titanium and other exotics.

So the SST (go find pictures) was reduced to a tiny needle that landed so hot that the cockpit had to hinge downward for the pilots to see.

Every flight was subsidized by the Anglo-French consortium which built them.

Over land, it could not do its supersonic thing - every country it wanted to go to had rules about sonic booms.

I once worked with an ultimate Yuppie - he had money enough and ego enough to buy a ticket. Unfortunately, it was not trans-oceanic, so the airspeed display in the cabin never went over .9 mach.

The Boeing entrant was named the 7007 (note the zeroes), if you want to search.

It was my suspicion that, because of the “civilized hostility” between the British and the French (France blocked the UK’s into the EEC (forerunner of the EU), for instance), it became a matter of one-upmanship as the realities of the limits and costs became obvious - neither was going to suggest the obvious - let’s not do this. Ever see two kids in a staring contest?

And the BD10J was a two-seater. All the billionaire who would drop a bit over a million to have one built would need to do was find a pilot qualified to fly it.

Pilots: aside from “Complex Aircraft”, what credentials would the FAA require to operate a 2 seater at mach 1.1?
It isn’t over 12,500 pounds, but I suspect some kind of endorsement would be required.

What did the Russians want to see before allowing the rider to take the stick in the MiG-29, for instance?

[Measure_for_Measure]

Nobel Laurette Kenneth Arrow was especially proud that the Council of Economic Advisers under him managed to kill the American SST program.
There’s another factor. The advantages of faster long haul east/west travel are mitigated by jet lag. Even if get to your destination instantaneously, you still need to adapt to the new time zone.