Search found 4373 matches

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by WIederling
Tue Nov 21, 2017 10:06 pm
Forum: Technical/Operations
Topic: Expert help: Wing aspect ratio/ spanlading vs induced drag
Replies: 9
Views: 406

Re: Expert help: Wing aspect ratio/ spanlading vs induced drag

A reduction in design weight doesn't automatically mean a higher aspect ratio. Aspect ratio is a property of the wing geometry (span^2 / area). Higher aspect ration ~= more transferred moment in the wing box ~= more stress ~= more material ~= more weight. there is no linear scaling of wings. The ov...

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by WIederling
Tue Nov 21, 2017 9:46 pm
Forum: Civil Aviation
Topic: Airbus weighs response if Boeing launches new mid-market model
Replies: 663
Views: 88431

Re: Airbus weighs response if Boeing launches new mid-market model

Amiga500 wrote:
It could also do with a touch more sweep, especially if you are increasing the t/c* to add more fuel.


Sweep goes down with better management of supercritical ( and other aero) features.
( look at the A340 laminar flow demonstrator. the outboard extensions are "scaled NB wings" )

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by WIederling
Tue Nov 21, 2017 5:17 pm
Forum: Technical/Operations
Topic: Operational Weak Spots of the Airbus A321NEO/LR.
Replies: 53
Views: 10526

Re: Operational Weak Spots of the Airbus A321NEO/LR.

Surely runway performance is more a function of lift/thrust rather than wheel loading, or do you mean the 4 wheel bogie allows more tilt? The 4 wheel bogie allows more wheels with brakes. Twice as many. Braking performance is determined by wheel load and rubber/tire surface stiction coefficient. yo...

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by WIederling
Tue Nov 21, 2017 12:14 pm
Forum: Military Aviation & Space Flight
Topic: A330MRTT Orders, Production And Testing
Replies: 185
Views: 51331

Re: A330MRTT Orders, Production And Testing

Lufthansa Technik has developed new cabin concepts for the A330 MRTT: a "governor" interior, a "rescue" interior, a "state" interior and a "trooper" interior. See https://www.flightglobal.com/news/articles/dubai-lufthansa-technik-announces-two-major-project-4...

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by WIederling
Tue Nov 21, 2017 10:00 am
Forum: Civil Aviation
Topic: Senate Tax Bill Opens Pandora's Box To Hurt ME3 Carriers
Replies: 83
Views: 8544

Re: Senate Tax Bill Opens Pandora's Box To Hurt ME3 Carriers

flyboy_se wrote:
I think US citizens have to pay taxes in the US even if working and living abroad. But other nationalities get tax free income.


Treaties on (no) double taxation. ( afaik with an eye to people. corporations less so? )

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by WIederling
Tue Nov 21, 2017 9:08 am
Forum: Civil Aviation
Topic: Why doesn't Russia make larger planes?
Replies: 64
Views: 11482

Re: Why doesn't Russia make larger planes?

F27500 wrote:
... Because who would buy them other than Russia? Most people don't trust Russian made planes. it would fail.


Do you have some corroborative statistics on that? ( "Most people don't trust Russian made planes." )

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by WIederling
Mon Nov 20, 2017 6:43 pm
Forum: Technical/Operations
Topic: Boeing and how it markets its 787 wings from an aerodynamics point of view
Replies: 46
Views: 3109

Re: Boeing and how it markets its 787 wings from an aerodynamics point of view

DocLightning wrote:
The stiffer Airbus A350 wing is heavier ..



IMU the A350 wing is the relatively lighter design. ( Look at OEW differences between 787-10 and A350-900 : minimal. )
A350 has more fuselage and quite a bit more wing area.

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by WIederling
Mon Nov 20, 2017 6:13 pm
Forum: Military Aviation & Space Flight
Topic: 748 or A380 Bomber Aircraft?
Replies: 35
Views: 1729

Re: 748 or A380 Bomber Aircraft?

NASA's SOFIA airborne telescope 747SP can open its main deck door in flight. SOFIA has a pressure bulkhead ahead of the telescope section. The telescope mounts into the bulkhead in a rather "involved" articulation. https://www.nasa.gov/sites/default/files/telescope-stability-rev.jpg https...

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by WIederling
Mon Nov 20, 2017 2:26 pm
Forum: Civil Aviation
Topic: Airbus Working With Emirates on New Order for Flagship A380
Replies: 807
Views: 102951

Re: Airbus Working With Emirates on New Order for Flagship A380

Just to remind you please they had planned some -700 as the smallest family member as well. So the -800 is no "shrink". I don't think the A380-700 or A3XX-50R ever went beyond some press releases and maybe PR 4color or two. IMU the -800 already is at the lower end of double decker efficie...

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by WIederling
Mon Nov 20, 2017 1:22 pm
Forum: Technical/Operations
Topic: RR Builds Next-Gen "Advance 3" Demo Engine
Replies: 38
Views: 6424

Re: RE: RR Builds Next-Gen

I note that the F104 jet engine had three spools , was made in 1968 Which engine do you mean? Speedbored wrote that RR had lots of patents around the three spool concept. I wanted to know which "F104" engine your were referencing. ( if there are valid patents around they are probably youn...

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by WIederling
Mon Nov 20, 2017 8:39 am
Forum: Military Aviation & Space Flight
Topic: Germany Considers Tornado Replacement
Replies: 450
Views: 33807

Re: Germany Considers Tornado Replacement

There are lot of countries that owe their freedom to hardworking and patriotic Americans. Oh, yeah. old story. Ask some Russians who really turned things on the nazis In the USA patriotism means freedom This is rather 1984ish. you've lost the meaning of freedom. patriotism replaces knowledge and un...

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by WIederling
Mon Nov 20, 2017 8:32 am
Forum: Technical/Operations
Topic: Boeing and how it markets its 787 wings from an aerodynamics point of view
Replies: 46
Views: 3109

Re: Boeing and how it markets its 787 wings from an aerodynamics point of view

I have a suspicion that the flex actually works into some of the performance as a nonplanar aerodynamic element that may reduce the sidewash outboard. But it's just a suspicion. . O I have a suspicion too! Not quite the same one as you so scientifically explain, however. So you two think that the b...

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by WIederling
Mon Nov 20, 2017 8:25 am
Forum: Civil Aviation
Topic: Airbus Working With Emirates on New Order for Flagship A380
Replies: 807
Views: 102951

Re: Airbus Working With Emirates on New Order for Flagship A380

VV wrote:
Don't you think it would be a huge mistake to design an airport exclusively for A380? It would be a pity for the airport if it can only operate A380.


Equal number of VLA and XVLA stands. This is public knowledge.

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by WIederling
Mon Nov 20, 2017 8:22 am
Forum: Civil Aviation
Topic: Airbus Working With Emirates on New Order for Flagship A380
Replies: 807
Views: 102951

Re: Airbus Working With Emirates on New Order for Flagship A380

I think it is extraordinarily unlikely that Airbus would have walked away from an offered deal, nor does it fit in with the Leahy comment - "ask Emirates." In retrospect and going by what the Boeing mouthpiece Saj Ahmad published recently this was Boeing's doing. and it seems to have been...

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by WIederling
Sun Nov 19, 2017 5:30 pm
Forum: Military Aviation & Space Flight
Topic: Germany Considers Tornado Replacement
Replies: 450
Views: 33807

Re: Germany Considers Tornado Replacement

https://en.wikipedia.org/wiki/Gulf_War_air_campaign Since we are discussing data points, consider that not one F117 was lost in Iraq despite it doing most of the heavy lifting in the first few days of the invasion. This is not lost on those that may have to penetrate contested airspace in the futur...

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by WIederling
Sun Nov 19, 2017 5:23 pm
Forum: Non-Aviation
Topic: Argentina's navy lost a submarine?
Replies: 25
Views: 1257

Re: Argentina's navy lost a submarine?

A satcom company has registered seven attempts to communicate, all within a few minutes. Because radio comms from a sub is heavily restricted, it means that the sub has managed to surface at some time. David Sorry, but it does not indicate the sub has managed to surface. What it does mean is the be...

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by WIederling
Sun Nov 19, 2017 2:19 pm
Forum: Civil Aviation
Topic: Emotional support pig removed from plane
Replies: 52
Views: 8905

Re: Emotional support pig removed from plane

There is something very very wrong with the liberals in the US. How long before we will have safe spaces on airplanes? Are the people that completely highjack provisions for real need really part of the "liberal" crowd? I'd more like associate the "everything and a large gob beyond t...

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by WIederling
Sun Nov 19, 2017 2:11 pm
Forum: Non-Aviation
Topic: Regional popularity of Spring vs. Fall fashion collections
Replies: 8
Views: 334

Re: Regional popularity of Spring vs. Fall fashion collections

seb146 wrote:
It gave me yet another reason why I will never ever do drag.


No category : "Schwarzenegger Drag for Casual Wear" :-)

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by WIederling
Sun Nov 19, 2017 12:07 pm
Forum: Technical/Operations
Topic: Why do the OEMs Outsource?
Replies: 17
Views: 1137

Re: Why do the OEMs Outsource?

I think we're going to see a trend away from outsourcing of major assemblies (wings, fuselages, etc.) in light of the trouble Boeing and others have had with that business model. Who else had major issues with outsourcing ( beyond some capitalist strife like seating the issue? ) Issue is/was locate...

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by WIederling
Sun Nov 19, 2017 11:12 am
Forum: Non-Aviation
Topic: Model 3 ‘Hell’ Is Burning Tesla’s Other Projects
Replies: 27
Views: 1242

Re: Model 3 ‘Hell’ Is Burning Tesla’s Other Projects

I reckon that you'd have to literally throw away a Tesla after 10 years or 120,000 miles. First issue will be getting spares for the electronics. ( Automatic gearboxes for Mercedes Model A,Vaneu,B Diesel (?only?) from a couple of years ago had (have?) issues with the controlling pcb inside the gear...

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by WIederling
Sun Nov 19, 2017 11:02 am
Forum: Technical/Operations
Topic: GE9X "a little" Heavier Than GE90-115B
Replies: 24
Views: 1800

Re: GE9X "a little" Heavier Than GE90-115B

And guys, please: it's "fewer blades" not "less blades." Sorry but that's just like nails on a chalkboard to me. Thanks for the hint and happy to give you some goose bumps :-) it is "fewer" for unitized things and "less" for "fully analog things" li...

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by WIederling
Sun Nov 19, 2017 10:58 am
Forum: Technical/Operations
Topic: RR Builds Next-Gen "Advance 3" Demo Engine
Replies: 38
Views: 6424

Re: RE: RR Builds Next-Gen

I note that the F104 jet engine had three spools, was made in 1968 (the RB-211 was 1969) , and patents last 14 or 20 years (depending on type). Which engine do you mean? https://en.wikipedia.org/wiki/Category:Three-spool_turbofan_engines Rush of engines around 1969.. 1972: Euro RB199/RB211 and Sovi...

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by WIederling
Sun Nov 19, 2017 10:38 am
Forum: Military Aviation & Space Flight
Topic: A400M Update
Replies: 472
Views: 66964

Re: A400M Update

Thus it will be the Germans that are delaying any relief for Airbus, and it's also (according to the article) the Germans who are the least likely to grant such relief. "Muttis Kindergeburtstag mit Topfschlagen" will come to an end tonight. Finale either cataclysmic or kumbaja. but defini...

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by WIederling
Sun Nov 19, 2017 10:21 am
Forum: Military Aviation & Space Flight
Topic: 748 or A380 Bomber Aircraft?
Replies: 35
Views: 1729

Re: 748 or A380 Bomber Aircraft?

Now if the bigger is better is taken out of the equation....what about attaching (or rather rebuilding) a redundant A345 with the body of an A330ST Super Beluga? Thinking Thunderbirds: Now you need to be able to open the maw in flight. :-) anyway. Beluga is a "volume transport". So, the &...

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by WIederling
Sun Nov 19, 2017 8:48 am
Forum: Military Aviation & Space Flight
Topic: Hypersonic wind tunnel
Replies: 4
Views: 454

Re: Hypersonic wind tunnel

https://en.m.wikipedia.org/wiki/List_of_wind_tunnels That is a swiss cheese kind of list. holes everywhere. i.e. it is extremely incomplete. ( Looked for the Dutch "freely flyable" windtunnel. not there ) https://www.dnw.aero/wind-tunnels/ Then for a hypersonic regime you can have rather ...

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by WIederling
Sat Nov 18, 2017 11:14 am
Forum: Technical/Operations
Topic: GE9X "a little" Heavier Than GE90-115B
Replies: 24
Views: 1800

Re: GE9X "a little" Heavier Than GE90-115B

zeke wrote:
I can understand how both statements can be true.


However you cut it:
Fan thrust for the 105klbs engine is lower than for the 115klbs GE90 one.
The change in bypass ration is just too small.
i.e. the GE90-115 has fan thrust in the range of 102.7..103.5 range
and the GE9X has 95.5 klbs ...

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by WIederling
Sat Nov 18, 2017 10:13 am
Forum: Non-Aviation
Topic: R u s s i a
Replies: 66
Views: 2069

Re: R u s s i a

I've gotta give you credit BawliBooch, that's some densely packed meaningless gibberish. You have talent, I believe you could nave a career ahead of you writing late night TV commercials. I get the impression you lack the basic requirement for a traditional critic: Actually understanding what you a...

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by WIederling
Sat Nov 18, 2017 10:07 am
Forum: Technical/Operations
Topic: GE9X "a little" Heavier Than GE90-115B
Replies: 24
Views: 1800

Re: GE9X "a little" Heavier Than GE90-115B

Less number of blades that per item are heavier would still allow for an overall lighter fan. But the heavier single blade ( from one blade out) and increased energy from higher rpm would then require a more substantial containment ring that as before has to cover 360° of circumference. Then I am th...

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by WIederling
Sat Nov 18, 2017 9:22 am
Forum: Technical/Operations
Topic: GE9X "a little" Heavier Than GE90-115B
Replies: 24
Views: 1800

Re: GE9X "a little" Heavier Than GE90-115B

per blade mass should be higher requiring more containment?

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by WIederling
Sat Nov 18, 2017 9:21 am
Forum: Technical/Operations
Topic: Why did the Connie fail as bomber vs. B29, B29 fail commercially vs. Connie?
Replies: 16
Views: 2466

Re: Why did the Connie fail as bomber vs. B29, B29 fail commercially vs. Connie?

BravoOne wrote:
The 377 came before the C97,


What I could garner:

( FF:1942) B29 -> (FF:1944) C97 -> (intro:1952) KC97
................................................... \ -> (FF:1947) B377

For the (K)C97 there must be some later "munge in" from the B50?

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by WIederling
Sat Nov 18, 2017 9:11 am
Forum: Military Aviation & Space Flight
Topic: 748 or A380 Bomber Aircraft?
Replies: 35
Views: 1729

Re: 748 or A380 Bomber Aircraft?

prebennorholm wrote:
The A380 fuselage is pressurized. The two floors are active structures keeping the fuselage in shape when pressurized.


Airlock style torpedo tubes ?

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by WIederling
Fri Nov 17, 2017 10:37 pm
Forum: Civil Aviation
Topic: Airbus Working With Emirates on New Order for Flagship A380
Replies: 807
Views: 102951

Re: Airbus Working With Emirates on New Order for Flagship A380

The 787 MOU is an attention grabbing message to Airbus and RR. My guess is that it might be about STC and/or his bosses reaching around Airbus management to get the BoD's attention. IMU what we see is battlefields intermeshing. Emirates and Airbus have the same objectives. Dissent is about who hold...

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by WIederling
Fri Nov 17, 2017 10:27 pm
Forum: Civil Aviation
Topic: Airbus Working With Emirates on New Order for Flagship A380
Replies: 807
Views: 102951

Re: Airbus Working With Emirates on New Order for Flagship A380

The T900 EP3 should be about halfway between the T700EP3 and T7000. That would give the T7000 about a 5% lower fuel burn than the T900 as a rough guess. I think you are way off. Your talking about 1.5 billion development cost between the two on SFC. STC bought a ~~4% PIP from what I could garner?

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by WIederling
Fri Nov 17, 2017 10:25 pm
Forum: Technical/Operations
Topic: Why is the A343 "underpowered"?
Replies: 76
Views: 4257

Re: Why is the A343 "underpowered"?

BTW are you admitting that the 500/600 were sub-optimal upgrades? Oh my that's bad, Airbus wasn't perfect at something. :| Beyond grating on some nerves elsewhere I didn*t do anything bad. So why should I admit anything. :-() The A340NG pushed Boeing to the 77W and extending ETOPS further. Airbus d...

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by WIederling
Fri Nov 17, 2017 7:08 pm
Forum: Military Aviation & Space Flight
Topic: 748 or A380 Bomber Aircraft?
Replies: 35
Views: 1729

Re: 748 or A380 Bomber Aircraft?

One problem with the 380 as a bomber is that the both floors are load-bearing. You can't remove the upper floor in a 380 to gain more space. David You can make it a hybrid bomber/ECM/EW/AWACS aircraft with the bombs in the lower deck and all the mission critical equipment and crew areas on the top....

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by WIederling
Fri Nov 17, 2017 7:04 pm
Forum: Technical/Operations
Topic: Why is the A343 "underpowered"?
Replies: 76
Views: 4257

Re: Why is the A343 "underpowered"?

zeke wrote:
An A343 one engine out has 102 klb of thrust (3x34klb) for 275 tonnes MTOW, the 77X has 105 klb one engine out for 351.5 tonnes.


minimum climb for the twin is lower than for the quad, isn't it?

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by WIederling
Fri Nov 17, 2017 6:55 pm
Forum: Civil Aviation
Topic: Dubai Air Show 2017 - Boeing Orders pt2
Replies: 91
Views: 19132

Re: Dubai Air Show 2017 - Boeing Orders pt2

There is also the significant boost in cargo hold capacity the 787-10 offers over the A330-300/900 (40 vs. 32). I'd question the useability of those extra 8 LD3 positions. 32 LD3 @ max tare are 51t @200kg/m³ it still presents 32t cargo 40 LD3 @ max tare are 63t, @200kg/m³ it still is 40t of cargo. ...

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by WIederling
Fri Nov 17, 2017 6:46 pm
Forum: Civil Aviation
Topic: Airbus Working With Emirates on New Order for Flagship A380
Replies: 807
Views: 102951

Re: Airbus Working With Emirates on New Order for Flagship A380

lowbank wrote:
Slug71,
If the T7000 was a fit for the A380 it would have been done at the same time as the A330neo. Instead they went for the EP3 PIP.


How do Trent1000TEN/Trent7000 compare to Trent900EP3 sfc wise?

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by WIederling
Fri Nov 17, 2017 6:38 pm
Forum: Technical/Operations
Topic: Why is the A343 "underpowered"?
Replies: 76
Views: 4257

Re: Why is the A343 "underpowered"?

By today's standards the A340-200/300 is a little shy on the T/W ratio. You are still missing the point. The A340 / A330 airframe layout is such that it needs less thrust. The A330 with the same fuselage and wing is relatively underpowerd ( by your metric ) too. 77W has T/W of .3 An early 230T A330...

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by WIederling
Fri Nov 17, 2017 5:22 pm
Forum: Civil Aviation
Topic: Dubai Air Show 2017 - Boeing Orders pt2
Replies: 91
Views: 19132

Re: Dubai Air Show 2017 - Boeing Orders pt2

There is also the significant boost in cargo hold capacity the 787-10 offers over the A330-300/900 (40 vs. 32). I'd question the useability of those extra 8 LD3 positions. 32 LD3 @ max tare are 51t @200kg/m³ it still presents 32t cargo 40 LD3 @ max tare are 63t, @200kg/m³ it still is 40t of cargo. ...

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by WIederling
Fri Nov 17, 2017 1:35 pm
Forum: Civil Aviation
Topic: Dubai Air Show 2017 - Boeing Orders pt2
Replies: 91
Views: 19132

Re: Dubai Air Show 2017 - Boeing Orders pt2

SCAT airlines orders 6 MAX jets with 5 options. http://.www.reuters.com/article/us-emirates-airline/kazakh-airline-scat-orders-six-boeing-jets-idUSKBN1DG1BM?il=0 SCAT Airlines really have an awkward name I would have expected a change of name by now as surely the meaning of the name has been made a...

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by WIederling
Fri Nov 17, 2017 11:12 am
Forum: Non-Aviation
Topic: R u s s i a
Replies: 66
Views: 2069

Re: R u s s i a

Perhaps Germany should go ahead and test drive some Russian military hardware? That would certainly insure no issues of interoperabiity in any future military partnerships with the East. Been there, done that. Was a wakeup call after reunification at least for some stuff. For other "bad bad ru...

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by WIederling
Fri Nov 17, 2017 10:30 am
Forum: Technical/Operations
Topic: How is seat pitch measured ?
Replies: 8
Views: 970

Re: How is seat pitch measured ?

It is measured typically from the front foot of a seat to the front foot of the seat behind it. You use a drawing to lay out where the seats will be locked into the seat tracks, and then use a tape measure to verify. The starting point to lay out the "LOPA" varies from operator to operato...

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by WIederling
Fri Nov 17, 2017 10:25 am
Forum: Civil Aviation
Topic: Court rules in favor of Kuwait Airways when it decided not to carry a Israeli passenger
Replies: 92
Views: 10201

Re: Court rules in favor of Kuwait Airways when it decided not to carry a Israeli passenger

mjoelnir wrote:
In all cases it is not the point of the person being Jewish, but having an Israeli passport.


The preferred way of media insertion is as a blatantly anti jewish / anti semitic activity.
( though note not everybody gets hit in the same way :-)

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by WIederling
Fri Nov 17, 2017 10:18 am
Forum: Non-Aviation
Topic: Looking for a New Car
Replies: 81
Views: 3240

Re: Looking for a New Car

jetwet1 wrote:
Difference of opinions then, I found it to be a slug, it needs a V8 or a turbo V6.


Where do you actually need all that power?
Racing from (red) traffic light to (the next red) traffic light?

You should brake less. That increases average speeds much more than putting the pedal to the metal. :-)

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by WIederling
Fri Nov 17, 2017 10:10 am
Forum: Non-Aviation
Topic: Sexual Assault - all of it
Replies: 91
Views: 2279

Re: Sexual Assault - all of it

"he sexually harassed me at work"? Is it up to me to prove my innocence or is it up to her to prove her claim? This is turning into a weaponized lever. Action happens just on the say so. See that other British minister getting chopped. Which once was the definition of "witch hunt&quo...

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by WIederling
Fri Nov 17, 2017 9:57 am
Forum: Military Aviation & Space Flight
Topic: 748 or A380 Bomber Aircraft?
Replies: 35
Views: 1729

Re: 748 or A380 Bomber Aircraft?

flyingturtle wrote:
One problem with the 380 as a bomber is that the both floors are load-bearing. You can't remove the upper floor in a 380 to gain more space.


As a cruise missile truck you wouldn't need that.
You'd have to design some nice mechanism to get them out the door though.

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by WIederling
Fri Nov 17, 2017 9:53 am
Forum: Technical/Operations
Topic: What is new in CFM LEAP-1A
Replies: 19
Views: 1522

Re: What is new in CFM LEAP-1A

lightsaber wrote:
...........

Thank you very much!

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by WIederling
Fri Nov 17, 2017 9:47 am
Forum: Civil Aviation
Topic: A319neo: will it enter into service or not?
Replies: 109
Views: 16015

Re: A319neo: will it enter into service or not?

It was bad enough when I found out they weren't going to build an A318NEO, now the A319NEO is on the rocks. We are moving towards a world where not only are all aircraft going to be twins, but they are all going to be "stretch" versions as well. Bullocks. low "cost" susceptibili...

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by WIederling
Fri Nov 17, 2017 9:40 am
Forum: Technical/Operations
Topic: Why is the A343 "underpowered"?
Replies: 76
Views: 4257

Re: Why is the A343 "underpowered"?

Ok how many pilots takeoff expecting to lose an engine EVERY TIME? You stay ready but if you actually think your going to lose an engine on every takeoff, maybe you shouldn't be flying. You have to expect loosing an engine every time. That is procedure. All your planning revolves around getting air...

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