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Absolutely. When I program in C++ on top of a sane foundation, I have no expectation of leaking memory any more so than I would in any other language. What I might say, though, is that C++ is a little less tolerant of divided attention. I rarely program in C++ while monitoring IM sessions or RSS feeds. Maybe the proper definition of a scripting language is a language where you can program approximately between the lines while moaning about your weekend hangover to your buddies list.

http://www.rotor.com/portals/12/Safety2002-2006.pdf

Accident rate for helicopters in America is 1 per 100,000 flying hours (11.4 S.R.Hadden-years) and trending downward. This includes the significantly more dangerous reciprocating designs. Few helicopter pilots chat on IM while flying, and only a vanishing minority shows up to work within 48 hours of non-subsistence substance ingestion.

I think C++ partially gets the bad reputation because so many dabblers out there have applied the worse-is-better philosophy to rotor proliferation. It's easy to architect a system in C++ with seven rotors. Not recommended; however, there is nothing to stop you but your own good judgment. Which seems to be the core problem with C++.

Larry is right on the money with his distinction about what a language forces you to say. C++ can become terrifically cumbersome in this department, to the point where C++ is a bad language choice by default unless you know in advance what abstraction C++ brings to the table (with some work) that simplifies your problem domain.

For example, as a C++ programmer I know exactly what Larry was talking about in his dispatch-by-committee passage. You can easily achieve this in C++ (on a compile-time basis for the idiom I have in mind): create a template function that does nothing but dispatch according to any set of rules concerning the types supplied that you can devise (which can be supplied to the template as policy templates, if you wish to do so). These dispatch functions can become ugly creations, but manageable if you are careful and not chatting on IM at the same time.

Personally, I wouldn't code in any multi-dispatch language with a lingering hangover from the previous morning.

One more parting shot about "leakage". It's like Gere's "The gun, the gun, the gun" ditty in Chicago: the purpose of his obsession with the gun is to dim the mind of the jury on related concerns such as motive and opportunity. I don't think about leakage when I'm writing C++ code. I think about correctness, establishing my post-conditions, and not violating my preconditions. Obviously, this can't be achieved if you are programming on top of a hideous library where a complete statement of such is too complex (or too mysterious) to write down for any given routine you need to call. But then you can't write correct code by any metric on top of such a library, so it fails my comprehension that any serious programmer would brag about not leaking memory faced with such an abomination. Many a sailor has drowned going to sea in a ship that never leaked.

PeterBrett says: Although I can't comment on the safety point, I'd be interested in seeing some numbers that support the claim that electric air conditioning is more efficient that the thermodynamic cycle currently used for aircraft air con.

I can't put my finger on the article in question, but Aviation Week covered this a few years ago. It was not a dramatic increase in efficiency, and the question was hotly debated (by, say, Airbus) there was some added efficiency. I believe that a big part of it was that tapping the bleed air of the engine just isn't an efficient way of generating power, even if the AC packs themselves were very efficient.

Part of it, too, was the advantage in not having to run hot high-pressure air lines through the plane, which were heavy and failure-prone.

Here's a press release from the manufacturer claiming dramatic efficiency gains -- more than I recall reading from the AvWeek article. Airbus, indeed, continues to claim that electric AC is not worth it. Given all the significant effort that has gone into this, though, I trust Boeing when they say that it is. The changes required to the engines to generate that much electricity were significant.

Thad Beier

Regarding the only interesting aircraft (the Fulcrum) I guess that was not completely correct. Besides a 18 months inspection period after the German reunification of one aircraft, all 20 MiG29A and 4 MiG29UB went 1991 in service with the German Air Force. One crashed in the late 90s and the remaining were given (i.e. sold for 1 EURO) to Poland in 2004...

Frank

(see http://www.flug-revue.rotor.com/FRHeft/FRHeft04/FR H0404/FR0404c.htm )

Cargo doesn't care about such things, which is why FedEx was one of the first A380 customers. Japan, if it weren't so loyal to Boeing, might have used an all-economy class A380 to replace their inter-city "bus" known as the 747-400D ("Domestic").

The best thing about the A380 is that it'll make for great subject matter for Hollywood. But for actual traveling, the choice will be between fewer stops and more scheduling flexibility vs. a bigger plane.

10 kw = 10000 watts = 10000 Joules/sec
200 watts = 200 J/sec

10000 J/sec / 200 J/sec = 50 seconds

...can be found here.

Well I also live pretty damn close to Captain's Cove * and I do know that there is a replica that has flown. Replica 21B, constructed in Whitehead's home town of Leutershausen, Germany, flew 500 meters in its longest test flight. This craft was first tested on September 12th, 1997, in Manching, Germany.

There are many reports that Whitehead did fly his craft in a controlled manner. The problem is that Whitehead was broke, convinced that there was no future in flight, and never got a photo of the plane in flight. It also didn't help that he was German and World War I broke out not too long afterwards. He never got the fame and publicity that the Wright brothers did and so his achievements were easily overshadowed by the Wright brothers. This includes deals made between the Wright brothers and the Smithsonian, where the Smithsonian was given an aircraft and equipment by the Wright family on condition that no one else would be put forth as flying before the Wright brothers. If the Smithsonian were to do so the donated aircraft and all would revert back to the Wright family.

And it's a damn shame that the HMS Rose had to get sold off, although it was good seeing her in "Master and Commander".

* Next town over, Stratford. My family used to dock a boat at the Cove before Captains Cove was built up with all the shops.

A nice article on Cryogenic Rocket engines is available here .

Dassault is planning a supersonic business jet.

You can buy a 100Kg ultralight helicopter. That's real.

Another thing that should be working by now, and isn't, is turbines for small aircraft. Light aircraft are still putt-putting around on reciprocating engines, decades after the big iron switched over.

Reference: Flug-Revue

This thing should have flown long ago. Maybe with lousy fuel economy, range, and operating cost, but it should have flown. Lots of small thrust-type air vehicles were built in the 1950s and 1960s, and many ended up at the Hiller Aviation Museum in Redwood City, CA. They have a Hiller Flying Platform, which flew quite successfully. They also have a Rotorcycle, which is a one-person portable helicopter from 1957.

Ultralight helicopters have been available for a few years now. Ones slightly heavier than the ultralight category are better machines, though.

Just charter a An-225

The article is slightly outdated, the investors apparently went ahead the reactivated the plane. They used it to fly some hundred tons of food to Afghanistan. While loading at Munich Airport it was photographed by a friend of mine... :-)

Regards, Ulli

In order to successfully design a high-speed aircraft, it's very important to know which direction it is going to fly. There are, to date, exactly zero exceptions to this rule.

I agree with your post, but I don't think you can make the claim that there are "zero exceptions". I believe that the SU-47 (formerly the SU-37) counts as an exception. It can completely flip around, or face backwards at 120 deg. Neat, huh?

I have met guys who work on development of Cryogenic rocket engines for space applications. One of the componets used in these is Hydrogen. From whatever I have heard, handling Hydrogen in any form is a VERY tricky thing, since leakages can easily cause major explosions...