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by flipdewaf
Sun Jun 16, 2019 10:02 pm
Forum: Technical/Operations
Topic: 787 vs A350 range
Replies: 358
Views: 61316

Re: 787 vs A350 range

To do a fair comparison we need the same assumption for both planes right? And flipdewaf has been doing that in his calculations throughout this thread by applying a common payload value to each frame. He's also using assumptions that much more closely mirror those used by airlines than either Airb...

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by flipdewaf
Sun Jun 16, 2019 9:38 pm
Forum: Technical/Operations
Topic: 787 vs A350 range
Replies: 358
Views: 61316

Re: 787 vs A350 range

Agree with you (flipdewaf) on the fuel volume. But if 268t can do 8100 still air SQ doesn't need to certify their A359ULR as 280t MTOW. Except SIN-LAX is not flown in "still air". And this means that the actual distance flown will be greater than the 7,621 nautical miles (nm) of the direc...

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by flipdewaf
Sun Jun 16, 2019 9:20 pm
Forum: Technical/Operations
Topic: 787 vs A350 range
Replies: 358
Views: 61316

Re: 787 vs A350 range

Boeing 787-9 ( 236 seats) @254t ~7600 nmi @260t ~8000 nmi Fixed it for you! Sent from my iPhone using Tapatalk ???? flip, the 236 seat 789 goes 7800+ on lhr leg for qants and it's takin off light apparently from what was posted on anet according also to info these flights are relatively high lf ua1...

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by flipdewaf
Sun Jun 16, 2019 8:33 pm
Forum: Technical/Operations
Topic: 787 vs A350 range
Replies: 358
Views: 61316

787 vs A350 range

mintxwb wrote:
Boeing 787-9 (236seats)
@254t ~7600 nmi
@260t ~8000 nmi

Fixed it for you!



Sent from my iPhone using Tapatalk

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by flipdewaf
Sun Jun 16, 2019 8:24 pm
Forum: Technical/Operations
Topic: 787 vs A350 range
Replies: 358
Views: 61316

787 vs A350 range

315 passengers, was the design payload at the 268 tonne W/V and promised to 7750 nm, Airbus exceeded that objective. (Please note Airbus increased their design payload subsequently from 315 pax to 325 pax, and increased the range it would carry). It will take a full cabin, that is what the performa...

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by flipdewaf
Sun Jun 16, 2019 8:57 am
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: Airbus A350-1000 Range Increase

I wonder if the range they quote is taking reserve fuel into account? If so, my simple calculation shows they're about 4~5 tons away from reaching Project Sunrise when using 159t OEW, 490kn, 7t/hr fuel burn (I've been conservative), 35t payload figure @ 8700nm. Not sure how much brochure range is n...

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by flipdewaf
Sun Jun 16, 2019 8:17 am
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Airbus A350-1000 Range Increase

I wonder if the range they quote is taking reserve fuel into account? If so, my simple calculation shows they're about 4~5 tons away from reaching Project Sunrise when using 159t OEW, 490kn, 7t/hr fuel burn (I've been conservative), 35t payload figure @ 8700nm. Not sure how much brochure range is n...

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by flipdewaf
Sat Jun 15, 2019 6:03 am
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

Having collected hundreds of data points in a previous argument for the 787 vs A350 I determined the Airbus brochure range is slightly optimisitc. so if I remember correctly you collected(selected is a better word) missions where the 359 was not operating at the edge of the payload-range envelope a...

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by flipdewaf
Fri Jun 14, 2019 9:38 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

8400 nm is the published design range at 316 tonnes. I havent said " cannot give a range number on any aircraft when asked (even the one you fly) bc there are too many variables, temperature, field altitude, flight levels, etc. etc." or anything remotely close to that recently. Considerin...

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by flipdewaf
Fri Jun 14, 2019 8:44 pm
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

A good challenger to these 787-8/9ER would be the A330-800ER. From a structural point of view, Airbus has the toolbox to make it a 275t (or even 276.5t) aircraft: it's the A343E (*), more specifically its wing and its center landing gear. This is to say that Airbus wouldn't need to spend a lot in r...

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by flipdewaf
Fri Jun 14, 2019 5:53 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

Actually, I see that Airbus is now advertising the A351 with a typical 3-class seating of 350-410 seats, while it used to advertise 365 seats previously. Considering 350 pax instead of 365 pax makes 1.5 t available for extra fuel. Together with the 3 extra tons of fuel made possible by the increase...

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by flipdewaf
Fri Jun 14, 2019 3:34 pm
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

It is always going to be more economical to fly the one stop on this route with current aircraft, no matter which aircraft is chosen. The difference is that premium traffic will pay for the direct flight and offset the cost of additional fuel burn. You Sure? Sent from my iPhone using Tapatalk 100%....

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by flipdewaf
Fri Jun 14, 2019 12:26 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

That is incorrect. It is correct. Speedbird52 asked if it takes the aircraft up to the range of the 778. It does not because the A350-1000 is still fuel limited. Carrying more payload at medium range is not what he asked. https://www.boeing.com/commercial/777x/#/technical-specs https://www.airbus.c...

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by flipdewaf
Fri Jun 14, 2019 12:12 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

Very interesting, also noting that the Fuel volume has stayed at 159000l. Is there some games at hand in making the range just top trump the 778X? Fred 159,000l definitely isn't enough to do London to Sydney. Looking at the A350 ACAP at max fuel the A350-1000 can fly 8500nm with 32,000kg of payload...

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by flipdewaf
Fri Jun 14, 2019 10:58 am
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

Back to the topic from baseless anti-A380 drivel. What is the approximate cut-off point for modern airlines where it is more economical fuel burn wise to fly in two separate stages like SYD-SIN-LHR rather than SYD-LHR. I'm predicting the whole concept of ULR to be outlawed or ar least becoming soci...

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by flipdewaf
Thu Jun 13, 2019 7:19 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

That range figure is likely just 350 passengers and their baggage. So 42,000kg using 100kg per passenger and 20kg per bag (those figures based on results of a 2009 IATA survey of airlines on the averages they use). Or have very small premium cabins. You are 100% correct. Realistically speaking with...

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by flipdewaf
Thu Jun 13, 2019 5:12 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

Very interesting, also noting that the Fuel volume has stayed at 159000l. Is there some games at hand in making the range just top trump the 778X? That range figure is likely just 350 passengers and their baggage. So 42,000kg using 100kg per passenger and 20kg per bag (those figures based on result...

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by flipdewaf
Thu Jun 13, 2019 3:04 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

Wonder what the payload looks like at those ranges, as the only purpose for that kind of range is ULH which is notoriously low payload, or use the extra MTOW for extra payload on typical long rang flights. Seems Airbus have really created and exceptionally flexible airplane with the A350. It was an...

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by flipdewaf
Thu Jun 13, 2019 2:51 pm
Forum: Civil Aviation
Topic: Airbus A350-1000 Range Increase
Replies: 111
Views: 18210

Re: a350-1000 range increase

Very interesting, also noting that the Fuel volume has stayed at 159000l. Is there some games at hand in making the range just top trump the 778X?

Fred

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by flipdewaf
Wed Jun 12, 2019 1:03 pm
Forum: Civil Aviation
Topic: Rumour: 777X First Flight Likely Delayed Due GE9X Issues
Replies: 165
Views: 27801

Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

[quote="Revelation"][/quote] I'm inclined to agree with you there, (I think I'm agreeing with you, I might be just agreeing with JL) that the A380 was somewhat sandbagged with poor engines (although that's partly Airbus's fault for chasing noise over optimum performance in my book). If you...

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by flipdewaf
Wed Jun 12, 2019 8:50 am
Forum: Technical/Operations
Topic: Landing fees in special cases
Replies: 13
Views: 1291

Re: Landing fees in special cases

My only real experience of this is from when I was training for my PPL. I think the invoices worked out as ~£20-24 handling fees for each flight (increase with inflation whilst training) but if I was doing circuits I was charged an extra £6/touch and go.

Fred

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by flipdewaf
Tue Jun 11, 2019 2:56 pm
Forum: Civil Aviation
Topic: Man arrested at Schiphol with loaded gun
Replies: 20
Views: 3813

Re: Man arrested at Schiphol with loaded gun

SCHIPHOL - A 35-year-old American was picked up at Schiphol on Monday with a weapon. Security personnel discovered the firearm with a cartridge holder with ammunition in his hand luggage at the security scan. The Royal Netherlands Marechaussee then took action, securing the backpack and arresting t...

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by flipdewaf
Tue Jun 11, 2019 2:35 pm
Forum: Non-Aviation
Topic: Tucker Carlson Bogeyman du Jour: the Metric System
Replies: 77
Views: 3616

Re: Tucker Carlson Bogeyman du Jour: the Metric System

And you forgot to mention another problem that used to be extremely annoying in the past. Different power voltages and frequencies in different countries. All that combined with different receptacles. Fortunately, nowadays all new travel items come with switching power supplies capable of handling ...

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by flipdewaf
Mon Jun 10, 2019 2:25 pm
Forum: Non-Aviation
Topic: Tucker Carlson Bogeyman du Jour: the Metric System
Replies: 77
Views: 3616

Re: Tucker Carlson Bogeyman du Jour: the Metric System

Yeah that's the claim. But it's not. It's not any better or more accurate or anything. It is just another system. I mean what would people say if aliens landed on earth and they used a base 16 numbering system? And based weights on helium atoms? Well a base 16 numbering system would lend itself to ...

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by flipdewaf
Thu Jun 06, 2019 10:42 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Re: Wind tunnel drag test

Is the fact that the wall is now touching the tips affecting your readings? You need to do multiple tests at various AoA to see if the 2d case confirms to the norms of a 2d aerofoil. Are you using a standard NACA profile? Does your data match with previous data taken, if not then you need to look at...

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by flipdewaf
Thu Jun 06, 2019 10:22 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Wind tunnel drag test

I didnt meassure zero AoA,but I can do it..Why do you ask? Can you explain why you think that 3D test must have greater drag ,what will increase drag if I didnt increase AoA on 3D airfoil? Because of induced drag. Are the aerofoils identical in profile and area? Are the measurements you have shown ...

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by flipdewaf
Thu Jun 06, 2019 9:58 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Re: Wind tunnel drag test

My results from wind tunnel test are: 2D test Lift:301 Drag:122 3D test Lift:214 Drag:94 (Note once again,AoA is same for both tests,I didnt increase AoA on 3D airfoil to compensate lift reduction because of tip pressure loss..) do you have data for 0 degrees? Fred Sent from my iPhone using Tapatal...

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by flipdewaf
Thu Jun 06, 2019 9:33 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Re: Wind tunnel drag test

3D test will show lower drag. Airfoil tips in 3D test are open end,so there is pressure loss on this region,there is no wall(end plate) which will stop this pressure to "escape",so drag and lift are reduced. (If we want have same amount of lift in both tests,than 3D will have greater drag...

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by flipdewaf
Thu Jun 06, 2019 9:13 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Re: Wind tunnel drag test

Don't you mean 2D will produce lower drag? I'd agree with that. Lol! Yes. Too much wine! Sent from my iPhone using Tapatalk 3D test will show lower drag. Airfoil tips in 3D test are open end,so there is pressure loss on this region,there is no wall(end plate) which will stop this pressure to "...

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by flipdewaf
Thu Jun 06, 2019 8:30 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Re: Wind tunnel drag test

3D year will produce lower drag. The fact that that both edges of the aero foil are touching the wall make it more approximate to a wing of infinite span which assuming incompressible low speed flow means no lift induced drag. Don't you mean 2D will produce lower drag? I'd agree with that. Lol! Yes...

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by flipdewaf
Thu Jun 06, 2019 7:42 pm
Forum: Technical/Operations
Topic: Wind tunnel drag test
Replies: 14
Views: 1003

Wind tunnel drag test

3D year will produce lower drag. The fact that that both edges of the aero foil are touching the wall make it more approximate to a wing of infinite span which assuming incompressible low speed flow means no lift induced drag. Fred Edit:Another assumption is that this airfoil is not a thin plate and...

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by flipdewaf
Thu Jun 06, 2019 2:53 pm
Forum: Technical/Operations
Topic: Operational Weak Spots of the Airbus A321NEO/LR Discussion Thread
Replies: 80
Views: 30904

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

Keesje, if you keep resurrecting dead threads like this you will find yourself as the focal point of a religion! Whilst I agree with the technical parts of what you have written with regards to Airbus putting a larger wing on the A32X series in terms of performace (range, field length etc) the bigge...

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by flipdewaf
Thu Jun 06, 2019 2:37 pm
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

https://en.wikipedia.org/wiki/Airbus_A350_XWB Let do some analysis based on more reliable data. Wiki states 1. MTOW - 316t 2. OEW - 158.8t 3. Range - 8400 nm 4. Seating -366 passengers (specs) 5. Project Sunrise seating - 300 passengers (estimated) For project sunrise, the still air range is 9200 n...

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by flipdewaf
Thu Jun 06, 2019 11:05 am
Forum: Technical/Operations
Topic: What are the FAA airport ID's used for?
Replies: 12
Views: 2495

Re: What are the FAA airport ID's used for?

I would imagine that there is something to do with standards and licensing as well as private vs public use and what operations the airfield can be used for as well as insurance liabilites. Can you buy a ticket to fly commercial there? IATA code Can you fly in to it and does it have a certain standa...

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by flipdewaf
Thu Jun 06, 2019 10:39 am
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

We don’t yet have an answer on integral fuel capacity of the Sunrise version of the A35K. You’d expect it to at least take the 165,000 litres of the 359ULR. We don’t know whether that’s the physical limit. Or whether it will require a belly tank. The wing chord on the -1000 is about 400 mm longer t...

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by flipdewaf
Thu Jun 06, 2019 10:18 am
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

The 777-8 does not need cargo fuel tanks. It has 197,977litres or 158T of fuel. It will comfortably be able to do the route with 25T of payload. The 777-8 burns less fuel than the 777-9. It is lighter and has less fuselage drag. The A350-1000 only has 158,000litres or 124T of fuel. It will need 15-...

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by flipdewaf
Wed Jun 05, 2019 10:04 am
Forum: Civil Aviation
Topic: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft
Replies: 1307
Views: 222499

Re: Updated: Qantas saying it is almost ready to select Project Sunrise aircraft

How long does it take to install/uninstall a row of economy seats ? If it is possible within short time, I could see QF configuring the last 4-5 rows of Y to be quickly removed for sunrise routes and installing them when operating on shorter routes. This space could be used for the wellness area. T...

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by flipdewaf
Wed Jun 05, 2019 10:01 am
Forum: Travel, Polls & Preferences
Topic: Your 2019 Booked/Flown Flights List
Replies: 199
Views: 23550

Re: Your 2019 Booked/Flown Flights List

Update to my list: Flown: January: KL1702 MAN-AMS B737-800 KL1551 AMS-LBA E170 AA735 MAN-PHL A330-200 AA1919 PHL-MCO A330-200 February: AA1848 MCO-PHL A330-200 AA734 PHL-MAN A330-200 March: QR22 MAN-DOH B787-8 QR904 DOH-MEL A380-800 JQ731 MEL-LST A320 JQ740 LST-MEL A320 QR905 MEL-DOH A380-800 QR27 D...

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by flipdewaf
Tue Jun 04, 2019 6:45 am
Forum: Non-Aviation
Topic: Ideas / input for bringing an elderly parent from Europe to live in the US
Replies: 13
Views: 650

Re: Ideas / input for bringing an elderly parent from Europe to live in the US

Does your dad want to?

Fred


Sent from my iPhone using Tapatalk

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by flipdewaf
Mon Jun 03, 2019 11:29 am
Forum: Civil Aviation
Topic: Reuters: Airbus pencils in orders for new A321XLR jet.
Replies: 197
Views: 44261

Re: Reuters: Airbus pencils in orders for new A321XLR jet.

We’re seeing a number of XLR stories coming out of IATA AGM in Seoul. It has the feel of a concerted effort to set the scene for a formal announcement in Paris. On the specifics: - Jetstar CEO is talking of 600nm additional range (over and above the LR) and using the XLR to replace 788s on routes f...

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by flipdewaf
Sat Jun 01, 2019 9:20 am
Forum: Civil Aviation
Topic: BA to use all retro 747s on a domestic flight
Replies: 52
Views: 13652

Re: BA to use all retro 747s on a domestic flight

A great idea by BA just wish they’d bring it to my home airport as it’s just over 2hrs to Manchester for some pics.

Fred


Sent from my iPhone using Tapatalk

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by flipdewaf
Sat Jun 01, 2019 6:13 am
Forum: Civil Aviation
Topic: Has grandfathering been taken too far?
Replies: 361
Views: 13247

Re: Has grandfathering been taken too far?

No, grandfathering should not be limited. Once an aircraft is in serial production and is plying routed around the world it will get safer and safer due to learnings and corrections, to then say you cannot build upon that safety but start with an unknown to me would be a more dangerous way to go. To...

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by flipdewaf
Sat Jun 01, 2019 5:37 am
Forum: Travel, Polls & Preferences
Topic: Born on an international flight
Replies: 18
Views: 2616

Re: Born on an international flight

My understanding is that the laws are the same as maritime law and the child would be legally entitled to citizenship of the nation of the registration of the vessel. As far as I'm aware, (outside of US) few countries entitle you to citizenship based solely on being born there. In most places entit...

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by flipdewaf
Fri May 31, 2019 9:08 pm
Forum: Travel, Polls & Preferences
Topic: Born on an international flight
Replies: 18
Views: 2616

Re: Born on an international flight

My understanding is that the laws are the same as maritime law and the child would be legally entitled to citizenship of the nation of the registration of the vessel. My friend Oliver was born on a flight from the US to the uk and as such is fully entitled to US citizenship. Fred Sent from my iPhone...

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by flipdewaf
Fri May 31, 2019 11:49 am
Forum: Civil Aviation
Topic: Climate activists plan to use drones at LHR
Replies: 52
Views: 6288

Re: Climate activists plan to use drones at LHR

They should be shot with organic fair-trade rubber bullets. Sorry, they won't be locally grown though. They should calculate the carbon footprint of carrying out the operation to prevent the use of drones at Heathrow and anyone who is arrested should be publicly labeled as being responsible for it....

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by flipdewaf
Fri May 31, 2019 11:42 am
Forum: Civil Aviation
Topic: Climate activists plan to use drones at LHR
Replies: 52
Views: 6288

Re: Climate activists plan to use drones at LHR

Considering any sort of drone activity near an airfield is highly illegal within certain restricted airspace, the response will be robust. Lessons were learnt after the LGW incidents I feel, and LHR is UK plc and I don’t think the Police/Army will hesitate to take swift action against anyone foolis...

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by flipdewaf
Fri May 31, 2019 11:33 am
Forum: Non-Aviation
Topic: Comfy, cushioned, long-lasting athletic socks
Replies: 8
Views: 654

Re: Comfy, cushioned, long-lasting athletic socks

Yeah...cushioned socks for athletic use? See, cushioned implies thick and cottony. That means they get, shall we say, "moist" and they stay "moist" (yeah, yeah, yeah...gross). See, the Champion ones I so loved were called "full cushion" on their website, and once out o...

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by flipdewaf
Fri May 31, 2019 11:09 am
Forum: Aviation Photography
Topic: Looking for Dulles IAD spotting info - hotels and stuff
Replies: 7
Views: 679

Re: Looking for Dulles IAD spotting info - hotels and stuff

https://airandspace.si.edu/udvar-hazy-center

Fred
-->

I have spotted at IAD about 13 years ago and no trip to IAD for spotting for an avi geek is complete without spending at least a day at the air and space museum.

https://airandspace.si.edu/udvar-hazy-center

Fred

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by flipdewaf
Fri May 31, 2019 9:48 am
Forum: Civil Aviation
Topic: Why does BA (and others) decide to use 20+ year old planes on specific popular routes?
Replies: 103
Views: 22044

Re: Why does BA (and others) decide to use 20+ year old planes on specific popular routes?

OK. And any considerations about the safety of a repeatedly overhauled old aircraft that had changes multiple times vs a new aircraft with all parts fresh from the factory? Sorry if this sounds an amateurish question, but better to know than not to know. Its actually often a little bit counter intu...

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by flipdewaf
Fri May 31, 2019 8:57 am
Forum: Civil Aviation
Topic: Climate activists plan to use drones at LHR
Replies: 52
Views: 6288

Re: Climate activists plan to use drones at LHR

They can use the law and surveillance to catch perpetrators. There may need to be new laws brought in to regulate the use of drones. Terrorist: a person who uses unlawful violence and intimidation, especially against civilians, in the pursuit of political aims. A suspected terrorist can be held for ...

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