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Schorsch

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  • in reply to: Virgin Orders A330 #534945
    Schorsch
    Participant

    I guess it is the weight variant with 238t MTOW.

    in reply to: 10-abreast A350! #535116
    Schorsch
    Participant

    I guess the average Asian passenger is still somewhat smaller than an 1970ies American or European.

    in reply to: F-22 can Super Cruise for only 100 Nautical Miles #2441000
    Schorsch
    Participant

    On that “mathematical” data, I assume you mean the data from the tables i gave. Now, if that’s the case, you’re wrong. The data from the table is a measured one, meaning in actual flying conditions with all variables applied, so it’s actually F-15’s thrust, not F100’s.
    This is why you get no net thrust above Mach 1.2 (visible in Tmil and Tidle comparsion). The turbine flow hit it’s physical limit and is unable to move faster, but then afterburner takes over and ignites (accelerates) the bypass flow.
    You can’t compare these charts to F119’s because F119 has a 0.2 bypass and this F100 has some ~0.7. The turbine mixture is more fuel saturated and grows more linear with speed, as opposed to F100’s.

    “With rising speed and above Mach 0,8 most of that nominal thrust is generated by the inlet- and outlet-systemand not by the installed engine.”

    Can’t say that I understood what you mean, so can you clarify that?

    Sens is correct in the sense that the true thrust data is hard to ontain. However, for practical purposes, the data you presented is useful and can be used to gain results with limited fidelity. The quoted effects of inlet and outlet design really kick in beyond M1.8. Up to that point some heuristic corrections on inlet pressure loss can be used.

    The difference between “cruise” and “supercruise” (TM) :), in theory, is 1 knot!
    One moment you’re subsonic and the other you’re supersonic and that makes SC merely a semantic category.
    In reality it isn’t so.
    The term supercruise is used to describe the aircraft’s ability to stay above its transonic velocity region (supersonic) without afterburner.
    This is important because the aircraft has increased drag (and other unwanted effects) in its transonic speed region and cruising at transonic speeds is never economic, due that drag.

    >>However, one should note that there are different transonic regions for different aircraft.<<
    This means, that the scale of transonic region vary according to aircraft’s aerodynamics. So, some aircraft experience transonic effects in a very narrow part of the envelope (f.e. Mach 0.95-1.05), while others, experience it the larger one (f.e. Mach 0.9-1.1, or much larger).
    So, there really isn’t a uniform number that encompasses all airframes.

    The importance of supersonic flight in weapon’s range terms, translates into giving the weapon maximum kinetic energy.
    In mathematical terms, this means that the missile adds it’s own max speed to the speed of the launching aircraft.
    F.e., if the missile’s top speed is Mach 3 and the launching aircraft’s is 0.9, the missile will fly Mach 3.9 at motor burnout and thus have greater range than if launched from static (SAM) installation.
    The only practical limit to this velocity synergy is the missile’s drag/structural limit.
    Supersonic flight doesn’t require of a missile to go overcome its transonic region by its own thrust, but by using launcher’s (aircraft’s) one and that conserves fuel and increases the range and overall energy level, which means better chance to score a hit.

    I would define supercruise as the ability to cruise behind the transonic drag peak, which translates into a Mach number of 1.1-1.3. In practical terms, what really matters is the specific range, the distance travelled for one unit of fuel.
    For 4th generation aircraft that dropped between 60 and 80% between M0.8 and M1.4, while the F-22 experiences a drop of roughly 40-50%.

    For advanced reading:
    http://forum.keypublishing.co.uk/showpost.php?p=1344565&postcount=27

    The relative change in specific range bears some dangers: by my defintion the B-58 was a supercruise aircraft, the SR-71 too. But both design have abismal specific range in subsonic regime. So, the ~50% rule should only be applied to aircraft of current technological standards with satisfying subsonic specific range.

    in reply to: New narrowbodies before 2022 #535400
    Schorsch
    Participant

    The same niche also includes A310 and B767, from 767-200 to 767-400. Oh, and DC-8-61 and -63.

    Theoretically, but both airliners are dominantly used for long range service. The B767 is replaced by B787-8.

    It has been launched and it has been sold. ANA continues to hold 25 firm orders. (JAL has cancelled theirs)

    ANA is in the position of getting to be the sole world operator of two airplane types (787-3 and MRJ). Let´s see what is the more efficient plane.

    If ANA makes a firm order, pays deposit and progress payments, but then cancels without good reason (such as Boeing´s failure to deliver on promised time or with promised performance), ANA loses their deposits, and Boeing earns money without selling any planes. However, ANA pays their deposits, keeps them with Boeing, and Boeing then cancels the airplane, is Boeing discharged by merely refunding the deposits? Or does Boeing have to compensate the customers over and above the refund of deposits?

    The design of a new wing costs several hundred million to one billion USD. For 25 orders Boeing will not commit, and ANA would go for a normal -8 with somehow less attractive cash operating costs.
    That of 860 orders only 25 are for the -3 indicates two things: either no-one wants it, or Boeing is not offering it any more but retains the orders from ANA as road kill.

    Comparing MRJ versus and B787-3 is like comparing apples with … pumpkins.

    in reply to: New narrowbodies before 2022 #535572
    Schorsch
    Participant

    ?????
    The 757 was designed to replace the 727-200…but hardly a 50s fuselage.
    Not even the 727 had that.

    But B707, 727, 737 and 757 use the same fuselage, which dimensions were set in the late 1950ies. It was OK back then, but airlines demand more today. The B757 was a good aircraft, but sales don’t lie and the fact that the single aisles cashed it big sales while the B757 was discontinued speaks for itself.

    I disagree, I think there is going to be a real need for a proper B757 replacement – whether this is part of the A320/B737 replacement remains to be seen. On that note, I think the replacement of those aircraft wil be split into two – 130-180 seats and 180-230 seats. I doubt the B787 will be used current niche routes that the B757 are used on, but there may be a niche market for a re-winged A321 – or B739 – until a definitive A320/B737/B757 replacement is found.

    I am not disputing that there is the need for a B757 replacement. I actually think there is a dire need for an aircraft that can hold around 200-220 people comfortably. Such a design needs to replace B757s, but also A300-600s. The problem is that for such capacity a single aisle is too small and a widebody too large, it is a compromise. And airlines don’t like this segment much. The B787-3 was aimed at that marked, but didn’t sell and I doubt it will ever be launched. We’ll see which concepts are proposed to the airlines.

    Airbus has the advantage that its A320 family has the optimum fuselage diameter, there ain’t much to change and only limited point in making it composite (you don’t save much weight but add headache). A re-winged A320 family using P&W GTF is a possible solution, especially as it would be a good stop-gap until 2020.

    in reply to: QANTAS to put extra A380 service on SYD-LAX route #535808
    Schorsch
    Participant

    Despite the obvious increase in capacity, could this move also be seen as a response to Delta’s new (ATL-)LAX-SYD service which is due to commence on 3rd July?

    What aircraft do they use? The first and business class in the new B777 looks very competitive, while it will have a hard time going against the A380.
    Economy with 3-3-3 @B777 should be similar standard as 3-4-3 @A380.

    P.S.: I have seen that Emirates really does have 3-4-3 seating in B777 economy. I know now what airline not to take.

    in reply to: New narrowbodies before 2022 #535826
    Schorsch
    Participant

    What about a rewinged A321, ideal B757 replacement!

    If you are really looking for an aircraft anchored around 200 Pax, you need to consider turn-around times. That becomes a prohibitive factor above 160 Pax in standard airline config (no EayJet). Other factors like undesirable fuselage length and flexibility become a factor. The B757 suffers from the late 1950ies fuselage, which sets clear limits on its attractiveness.

    The A321 and B737-900 are rather stop-gab solutions, especially Boeing never really gave a sh#t on its -900 until a few years ago.
    The A321 is long-time favorite on short range trunk routes. It replaces the A300-600 at Lufthansa (while it is not really a replacement).

    in reply to: New narrowbodies before 2022 #535965
    Schorsch
    Participant

    Why develop anything for the short term?
    If Boeing and Airbus are going to introduce more efficient transports in “just” 10-12 years, why would anyone buy a less efficient AC as a stop gap?

    It’s not like any of the new players (Brazil, Canada, China, Russia) are going to leapfrog the big guys with new airframe or engine technology.

    Just wait until 2020 and the new technologies will be in a range of narrowbodies….just in time to replace existing fleets of late model 737s & A320 series planes.

    Especially, as on the short legs, fuel consumption doesn’t really matter.

    The topic of the next single aisle is really a big one. I don’t think this forum has the ability to discuss it, the lack of specific knowledge and experience becomes apparent in each thread. Really, you need some basics on aircraft design, and the trades involved. Not a layman’s task.

    in reply to: New narrowbodies before 2022 #535966
    Schorsch
    Participant

    Definitely expect variants of the SSJ and MRJ.

    I won’t put the MRJ out of contention so quickly, i know aty least 2 airlines in India itself who are looking at the MRJ seriously for future fleet plans.

    And as far as India goes, we won’t be heading anywhere substantial in civil aviation products for at least a decade or so.

    Considering wing load and fuselage dimensions, both have definitive limits. There is not so much fantasy in it.

    in reply to: New narrowbodies before 2022 #536160
    Schorsch
    Participant

    B757 is out of production, and out of development. Which means that a newbuilt Tu-204SM is a much better alternative to an old 757 than a Tu-204 was to a new 757.

    Who would be so lost and desperate to have these funny Russian engines under his wing?
    I rather take a used B757 any time over the 1to1 copy of the Russians.
    As we can see, most airlines see it the same way.
    Buying a Tu204 is like paying for scrap metal.

    As for A321, it has never matched the MTOW of 757, nor range. Since there is no new narrowbody from Airbus nor Boeing before 2022, it seems that Airbus is not going for a new wing to an A320 757 replacement either.

    The A321 does make 2500nm with full passenger load.
    So for those sectors, the A321 perfectly matches the B757.

    Guess why the B757 is out of production?
    Ain’t it funny that the B757, which was the last standardbody aircraft of Boeing, and the previous one survived it.

    in reply to: New narrowbodies before 2022 #536186
    Schorsch
    Participant

    Sukhoi Superjet. Any stretches (SSJ-100-110? SSJ-110-130?)?
    May take away some business from B737-700 and A319, and attract some airlines in less attractive markets.

    What about Tu-204 upgrades?
    Doomed. Why not get an A321 or the B757?

    Tu-334?
    Failed invention.

    MS-21?
    More a will, with the Russian habit of making a big proposal and then falling short. I can’t see an “MS-21” beating current narrowbodies by margin.

    ARJ-21?
    Great: the DC-9 with CF-34 engines. Will change aviation as we know it.

    Mitsubishi MRJ?
    Japanese aircraft always fail, I don’t know why, but it is masterful engineering plus pityful marketing and bad luck.

    Bombardier Cseries? Shall Cseries be stretched beyond CS300 any time between 2013 and 2022?
    Best contender. If bombadier survives the next 3-5 years, it might sell a 4-digit amount. Still, the C-Series would be beaten by future A&B products, but the dynamics of the market give Bombadier a good chance to earn some Canadian Dollars.

    Comac 919?
    The MS-21 of China.
    Funny to announce the great new aircraft while struggling to master the certification of the DC-9/CF34.

    Anything from Embraer?
    Possibly, but they cannot offer anything better than the C-Series, and they cannot compete versus A&B in financing and technical capability.

    Any completely new manufacturers?
    Maybe some state-driven money combustor from India. But without government willing to waste big money, no new manufacturer emerges.

    in reply to: IFLC to cancel A380 order? #536370
    Schorsch
    Participant

    In reference to Schorsch’s and B-I-O’s comments: I hear time and again the “passenger preference” argument, yet have never read or seen this concept backed up by an independent (non manufacturer) study.

    I have worked for an airline for almost 25 years, and my mother was a travel agent for 25 years, and our personal experience (and every independent study I have ever seen) says that the first three factors influencing ticket sales, are price, price, and price. (in that order, sarcasm intended…:))

    No doubt the A380 is a nice ride, probably better than any competitor. I don’t see that fact trickling down to more orders or market success.

    399 economy seats.
    Supports your statement.

    in reply to: All-coach A380 at last! #536562
    Schorsch
    Participant

    Air France already ignores the passengers who want to travel in F, and carries an unreasonably small proportion of seats in C (14 out of 472 in 777-300ER, 17 out of 477 on 747-400). Air Austral mainline does likewise. And Corsair flies there ignoring C as well (only premium economy).

    Thus Air Austral might make the next move of flying an A380 with no premium class at all, and directing both C and premium economy passengers to fly their mainline…

    I wouldn’t say ignore, I guess if enough people want to go, they install a big shiny first class. Apparently, people flying to Reunion are more the stingy type.

    in reply to: All-coach A380 at last! #536595
    Schorsch
    Participant

    Well considering the competition already on the route from the likes of Air France, I find the idea of an A380 operating the route very hard to believe!
    Not only that, but a reasonable portion of those pax will want to travel in C/F classes, why ignore them?

    I don’t know the traffic volume, but I guess the window for travel is limited (to have acceptable departure and arrival times). The flight is 10 hours, so quite a bit. I think with 800 people on board you can make quite competitive pricing, something where one who operates B747 or B777 really has a hard time to compete against, especially when fuel prices are high (the A380 burns 20% less than B747-400, 11% less than B777-300ER). At the same time, the A380 with 3-4-3 on main deck and 2-4-2 on upper deck is reasonably comfortable, while a B747 with 3-4-3 is more crammed and a B777 with 3-4-3 is close to unacceptable for a 10 hour flight.
    Different than some other wide bodies, the A380 is a very good economy class aircraft!

    Besides: Both the B777-300ER and the B747-400 get some payload-range issues at max passenger load, at least for a 5000nm trip like Paris to Reunion.

    in reply to: IFLC to cancel A380 order? #536747
    Schorsch
    Participant

    Never via Kobenhavn?

    How would the seat capacity of one A380-800 and one A330-200 combined compare against 2x 747? And are airlines able to make a sensible interior design and ticket pricing such that rich passengers in First, Business, Premium Economy and full fare economy can fly in exact same comfort at either time they like, while discount economy only flies on the A380?

    Example Singapore Airlines A380: First and Business class seats are not so much more than on a B747-400, but with much more comfort, making it a special experience. Actually, the Business Class on the A380 exceeds the First class of a few years ago. And the rest is economy. 399 economy seats.
    Maybe a trend: offer the premium travelers an experience they are willing to pay for, and offer a big bunch of affordable economy seats (which still have a competitive comfort level, economy in A380 is considered quite human; no 2-5-2 cattle class).

Viewing 15 posts - 436 through 450 (of 3,480 total)