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x1234
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DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 6:47 pm

With UA about to start in a few weeks EWR-JNB service using a upgraded performance package from Boeing on the B789 to squeeze out extra range and payload so with the hot & high conditions in JNB, the B789 can take near full payload JNB-EWR. I know DL is disadvantaged with the A359 but I wonderw why the A359 cannot make JNB-ATL back non-stop when SAA used a A359 for JNB-JFK. Anyone have payload data on SAA's JNB-JFK A359? The CPT stop definetly puts DL on a disadvantage compared to UA.
 
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Polot
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 6:51 pm

ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.
Last edited by Polot on Sat Dec 05, 2020 6:52 pm, edited 1 time in total.
 
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snoopaloop
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 6:53 pm

Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Think DL would consider moving the flight to JFK instead? Or the ATL connections are what they really need?
 
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Polot
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 6:58 pm

snoopaloop wrote:
Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Think DL would consider moving the flight to JFK instead? Or the ATL connections are what they really need?

It wouldn’t exactly surprise me if DL eventually moves it to JFK, especially with SAA no longer having A350s and basically being a shell of its self.
 
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JerseyFlyer
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 8:22 pm

In the present climate we will not know if it is UA or DL that is at a disadvantage until we learn moree about the pax numbers and revenue each is achieving on USA -SA overall.

I can see a split business or vacation trip from US to JNB and CPT all on US metal proving attractive to many.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 8:30 pm

Polot wrote:
snoopaloop wrote:
Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Think DL would consider moving the flight to JFK instead? Or the ATL connections are what they really need?

It wouldn’t exactly surprise me if DL eventually moves it to JFK, especially with SAA no longer having A350s and basically being a shell of its self.



The Atlanta route is perfectly fine. I think they'd just run JFK alongside ATL.
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 05, 2020 8:59 pm

One might think that DL's ten years of non-stops from JNB would buy it awareness in the market that UA will lack.
 
JohanTally
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sun Dec 06, 2020 2:43 am

Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Are the DL A359s 268t variants because the 280t MTOW should have a 400nm range advantage over the 789
 
Chaostheory
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sun Dec 06, 2020 3:23 am

JohanTally wrote:
Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Are the DL A359s 268t variants because the 280t MTOW should have a 400nm range advantage over the 789


Higher TOW options become meaningless when you don't have the performance to lift the weight.

That said, the A359 has far better field and climb performance than the 789 under hot/high conditions.
 
DylanHarvey
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sun Dec 06, 2020 10:28 am

Even the 77L struggled on this route, payload from 28-32t as posted in a thread. If a 77L can’t guarantee nonstop 100% of a time, it’s a hard time for another aircraft, The other issue is I read somewhere that Delta require more reserve fuel which to knock about 3 to 5 tons of payload off of a certain flight which is a hindrance at the end of the pay load range chart. Don’t quote me on that but I just heard it somewhere. I have seen around 12 tons of reserve on a Delta 359.
 
AF022
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 07, 2020 8:25 pm

Maybe i missed this, but aren't they changing it to ATL-JNB-CPT-ATL to avoid JNB high and hot departure back to ATL?
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 07, 2020 10:35 pm

AF022 wrote:
Maybe i missed this, but aren't they changing it to ATL-JNB-CPT-ATL to avoid JNB high and hot departure back to ATL?


Yes.
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 9:33 am

x1234 wrote:
With UA about to start in a few weeks EWR-JNB service using a upgraded performance package from Boeing on the B789 to squeeze out extra range and payload so with the hot & high conditions in JNB, the B789 can take near full payload JNB-EWR. I know DL is disadvantaged with the A359 but I wonderw why the A359 cannot make JNB-ATL back non-stop when SAA used a A359 for JNB-JFK. Anyone have payload data on SAA's JNB-JFK A359? The CPT stop definetly puts DL on a disadvantage compared to UA.


What sort of payload will the 789 manage out of JNB?
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 9:48 am

DylanHarvey wrote:
Even the 77L struggled on this route, payload from 28-32t as posted in a thread. If a 77L can’t guarantee nonstop 100% of a time, it’s a hard time for another aircraft,.


Not in JNB, where the 772L/F can´t take of anywhere near MTOW before running into their tire speed limit according to Boeing ACAP.

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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 10:21 am

Prop wrote:

What sort of payload will the 789 manage out of JNB?


I personally doubt the “B789 can take near full payload” claim, and the amount of payload out of JNB varies a lot depending on time of day and time of year.
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 10:22 am

tommy1808 wrote:
DylanHarvey wrote:
Even the 77L struggled on this route, payload from 28-32t as posted in a thread. If a 77L can’t guarantee nonstop 100% of a time, it’s a hard time for another aircraft,.


Not in JNB, where the 772L/F can´t take of anywhere near MTOW before running into their tire speed limit according to Boeing ACAP.

best regards
Thomas

Delta have goodrich tires which increase the tire speed limit slightly out of JNB. Either way the 77L has made multiple stops enroute, it might be the most challenging ultra long-haul route in the whole world. Atlanta to Johannesburg is not a stretch really.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 12:50 pm

JohanTally wrote:
Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Are the DL A359s 268t variants because the 280t MTOW should have a 400nm range advantage over the 789


The 280t out of JNB is almost irrelevant. You will seldom get more than 274t airborne off 03L and about 270t off 21L. On a cold day you could get lucky. I can’t see the B789 taking full payload out of JNB on a 15-16hr flight. I am happy to be wrong though.
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 5:08 pm

T54A wrote:

The 280t out of JNB is almost irrelevant. You will seldom get more than 274t airborne off 03L and about 270t off 21L. On a cold day you could get lucky. I can’t see the B789 taking full payload out of JNB on a 15-16hr flight. I am happy to be wrong though.


B789 is at most 254t. JNB it is not a problem for 789, maybe 77L and A350 can't take off at full MTOW, but certainly B789 can.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 7:34 pm

moyangmm wrote:
T54A wrote:

The 280t out of JNB is almost irrelevant. You will seldom get more than 274t airborne off 03L and about 270t off 21L. On a cold day you could get lucky. I can’t see the B789 taking full payload out of JNB on a 15-16hr flight. I am happy to be wrong though.


B789 is at most 254t. JNB it is not a problem for 789, maybe 77L and A350 can't take off at full MTOW, but certainly B789 can.



I think that 270t/275t number is predicted on a A359, I.e. and A359 can take 270-274t out of JNB. The 787 would probably see a similar fall off as compared to MTOW of the 787.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 7:38 pm

T54A wrote:
JohanTally wrote:
Polot wrote:
ATL is ~400nm further from JNB than JFK/EWR are. Those extra 400 nm matter a lot when you are at the edge of the aircraft’s performance and why the A359/789 can do JNB-EWR/JFK nonstop with acceptable payload penalties but not JNB-ATL nonstop.

DL is not at a disadvantage due to the aircraft- a A359 will haul more than a 789 on the same route. They are just at a disadvantage over their choice of US destination.


Are the DL A359s 268t variants because the 280t MTOW should have a 400nm range advantage over the 789


The 280t out of JNB is almost irrelevant. You will seldom get more than 274t airborne off 03L and about 270t off 21L. On a cold day you could get lucky. I can’t see the B789 taking full payload out of JNB on a 15-16hr flight. I am happy to be wrong though.


My apologies. I was referring to the A359.
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gloom
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Tue Dec 08, 2020 8:12 pm

moyangmm wrote:
B789 is at most 254t. JNB it is not a problem for 789, maybe 77L and A350 can't take off at full MTOW, but certainly B789 can.


Funny that Boeing seems to disagree.

At 3000ft, ISA+15 you hit brake energy limit, see Boeing's ACAPS. JNB is way above.

But yeah, sure, some people will never learn. :P

Adam
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Wed Dec 09, 2020 2:57 pm

moyangmm wrote:
B789 is at most 254t. JNB it is not a problem for 789, maybe 77L and A350 can't take off at full MTOW, but certainly B789 can.



By my eyeball on the Boeing ACAPs for the 787 with the high thrust engines on a standard day and dry runway the 787 can take off on the longest runway at 530 000lb or around 241T so nowhere near MTOW.

The A359 according to the Airbus ACAPs can take off with around 595 000lb or 270T. The hotter it gets the worse it gets for performance so when there is a heatwave, which there has been a few the past few years, the performance of both will suffer.

If you want that as a percentage hit to MTOW, I make it the 787 loses about 5% and the A359 about 4% of the MTOW they can take. Not much difference, but when your flight is at the outer edge of performance, every little bit is important. This isn't the 77W of EK taking off at 2pm but only flying for 8 hours. BTW, eyeballing again the 77W in summer in JNB on a hot day can take 700 000lb or 317T, losing about 10%. On a standard day, the evening takeoff, it can take just a little more as the problem is the tire speed limit for the 77W. My eyeball estimate is maybe 707 000lb or 320T or about a 9% loss against the MTOW.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Wed Dec 09, 2020 9:30 pm

enzo011 wrote:
By my eyeball on the Boeing ACAPs for the 787 with the high thrust engines on a standard day and dry runway the 787 can take off on the longest runway at 530 000lb or around 241T so nowhere near MTOW.


ACAPS says it's even lower, I'd estimate for 237-239T (at ISA+15, approx 5500ft altitude, 14.5k ft runway length). See table 3.3.14.

Cheers,
Adam
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Fri Dec 11, 2020 2:33 am

As someone mentioned SAA flies JNB-JFK with an A359 which is over 400 nm shorter than JNB-ATL. That additional flight time to ATL would roughly amount to 5.5-6 tons of additional fuel or less payload. That is not insignificant over such long distances.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Fri Dec 11, 2020 7:28 am

DLH has the perfect plane(s) out of JNB : 747-8I, and if demand soars due covid19 : A343., see : https://www.flightradar24.com/data/flights/lh573
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Fri Dec 11, 2020 8:31 am

ElroyJetson wrote:
As someone mentioned SAA flies JNB-JFK with an A359 which is over 400 nm shorter than JNB-ATL. That additional flight time to ATL would roughly amount to 5.5-6 tons of additional fuel or less payload. That is not insignificant over such long distances.


Using Flysmart the difference between flying 7333 nm and 6943 nm is 3.9 tonnes in 48 minutes, the "extra" distance is being flown at the end of the flight when the aircraft is flying up at FL430. Absolute maximum payload over JNB-EWR would be around 49 tonnes, over JNB-ATL 45 tonnes, that is limited by RTOW, in reality that would drop further due to diurnal density height changes.

747classic wrote:
DLH has the perfect plane(s) out of JNB : 747-8I, and if demand soars due covid19 : A343., see : https://www.flightradar24.com/data/flights/lh573


OPT has the 747-8 RTOW at 405 tonnes off 03L, 15 deg C, 1013, nil wind, packs off, favorable CG.
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ElroyJetson
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 12, 2020 2:01 am

zeke wrote:
ElroyJetson wrote:
As someone mentioned SAA flies JNB-JFK with an A359 which is over 400 nm shorter than JNB-ATL. That additional flight time to ATL would roughly amount to 5.5-6 tons of additional fuel or less payload. That is not insignificant over such long distances.


Using Flysmart the difference between flying 7333 nm and 6943 nm is 3.9 tonnes in 48 minutes, the "extra" distance is being flown at the end of the flight when the aircraft is flying up at FL430. Absolute maximum payload over JNB-EWR would be around 49 tonnes, over JNB-ATL 45 tonnes, that is limited by RTOW, in reality that would drop further due to diurnal density height changes.

747classic wrote:
DLH has the perfect plane(s) out of JNB : 747-8I, and if demand soars due covid19 : A343., see : https://www.flightradar24.com/data/flights/lh573


OPT has the 747-8 RTOW at 405 tonnes off 03L, 15 deg C, 1013, nil wind, packs off, favorable CG.



Your figures are off a bit. The difference is 409 nm difference between the city pairs, not 390 nm as you indicated. Also your total flight time is inaccurate as well. The average flight time difference is 53 minutes not 48. See links below for the correct information. You may want to rerun your numbers so they are accurate.



https://www.airmilescalculator.com/distance/jnb-to-jfk/


https://www.airmilescalculator.com/distance/jnb-to-atl/
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 12, 2020 11:31 am

ElroyJetson wrote:
zeke wrote:
ElroyJetson wrote:
As someone mentioned SAA flies JNB-JFK with an A359 which is over 400 nm shorter than JNB-ATL. That additional flight time to ATL would roughly amount to 5.5-6 tons of additional fuel or less payload. That is not insignificant over such long distances.


Using Flysmart the difference between flying 7333 nm and 6943 nm is 3.9 tonnes in 48 minutes, the "extra" distance is being flown at the end of the flight when the aircraft is flying up at FL430. Absolute maximum payload over JNB-EWR would be around 49 tonnes, over JNB-ATL 45 tonnes, that is limited by RTOW, in reality that would drop further due to diurnal density height changes.

747classic wrote:
DLH has the perfect plane(s) out of JNB : 747-8I, and if demand soars due covid19 : A343., see : https://www.flightradar24.com/data/flights/lh573


OPT has the 747-8 RTOW at 405 tonnes off 03L, 15 deg C, 1013, nil wind, packs off, favorable CG.



Your figures are off a bit. The difference is 409 nm difference between the city pairs, not 390 nm as you indicated. Also your total flight time is inaccurate as well. The average flight time difference is 53 minutes not 48. See links below for the correct information. You may want to rerun your numbers so they are accurate.



https://www.airmilescalculator.com/distance/jnb-to-jfk/


https://www.airmilescalculator.com/distance/jnb-to-atl/


Interesting how the website you are using returns different values than the Airbus Flysmart package that Zeke is using.

Zeke did quote his source so he cannot just adjust his figures - just as you cannot.
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 12, 2020 4:16 pm

ElroyJetson wrote:


Your figures are off a bit. The difference is 409 nm difference between the city pairs, not 390 nm as you indicated. Also your total flight time is inaccurate as well. The average flight time difference is 53 minutes not 48. See links below for the correct information. You may want to rerun your numbers so they are accurate.



https://www.airmilescalculator.com/distance/jnb-to-jfk/


https://www.airmilescalculator.com/distance/jnb-to-atl/


Using the same website you linked I get this output, please note my post stated JNB-ATL and JNB-EWR, not JNB-JFK


There are several ways to calculate distances between Johannesburg and Atlanta. Here are two common methods:

Vincenty's formula (applied above)
8439.340 miles
13581.801 kilometers
7333.586 nautical miles
Vincenty's formula calculates the distance between latitude/longitude points on the earth’s surface, using an ellipsoidal model of the earth.

There are several ways to calculate distances between Johannesburg and Newark. Here are two common methods:

Vincenty's formula (applied above)
7989.842 miles
12858.405 kilometers
6942.983 nautical miles
Vincenty's formula calculates the distance between latitude/longitude points on the earth’s surface, using an ellipsoidal model of the earth.

7333.586 nautical miles minus 6942.983 nautical miles = 390.603 nm, I would think most people on here would accept that is accurate enough to the 390 nm I stated.

As for the flight time, it’s straight from Flysmart, ie, manufactures data.

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LH707330
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 12, 2020 6:44 pm

One metric to think about is what fraction of its MTOW can a given design lift out of JNB, i.e. JNB TOW / ISA SL MTOW. I'd be curious to see how all the designs stack up. At the end of the day, the important metric is whether your TOW is enough to lift whatever payload you want to fly profitably.
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 12, 2020 9:35 pm

The primary issue out of JNB isn't the absolute performance of the aircraft, but mostly gets down to tire limitations. Hence why DL got the radials on the 77Ls. If UA and DL can put similar upgrades on their 789s and A359s respectively, both aircraft should do fine.
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sun Dec 13, 2020 12:16 am

N1120A wrote:
The primary issue out of JNB isn't the absolute performance of the aircraft, but mostly gets down to tire limitations. Hence why DL got the radials on the 77Ls. If UA and DL can put similar upgrades on their 789s and A359s respectively, both aircraft should do fine.


The A350 is not tyre speed limited out of JNB
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VSMUT
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 12:43 am

zeke wrote:
N1120A wrote:
The primary issue out of JNB isn't the absolute performance of the aircraft, but mostly gets down to tire limitations. Hence why DL got the radials on the 77Ls. If UA and DL can put similar upgrades on their 789s and A359s respectively, both aircraft should do fine.


The A350 is not tyre speed limited out of JNB


What is the limiting factor for the A350 out of Johannesburg?
 
Okcflyer
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 1:34 am

VSMUT wrote:
zeke wrote:
N1120A wrote:
The primary issue out of JNB isn't the absolute performance of the aircraft, but mostly gets down to tire limitations. Hence why DL got the radials on the 77Ls. If UA and DL can put similar upgrades on their 789s and A359s respectively, both aircraft should do fine.


The A350 is not tyre speed limited out of JNB


What is the limiting factor for the A350 out of Johannesburg?


A359 has impressive low speed characteristics. My guess is engine-out second stage climb performance. Just not enough thrust.

Keep in mind the 77W really has excess thrust. It’s wing loading is very high resulting in high speeds, resulting in higher than normal acceleration rates, which require a lot of thrust. It’s L/D also isn’t the best at low speeds. However, the monster GE 115’s produce more than enough to make up for the needs. This is one such reason it hits a tire speed limits, that need for high speed.
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 5:23 am

VSMUT wrote:
What is the limiting factor for the A350 out of Johannesburg?


Takeoff performance includes the runway performance as well as the initial climb performance. For the initial climb performance there is a horizontal and vertical buffer surrounding the predicted flight path.

The performance software is saying that it is limited by an obstacle outside the airport that impinges this horizontal or vertical buffer.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
VSMUT
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 9:22 am

zeke wrote:
VSMUT wrote:
What is the limiting factor for the A350 out of Johannesburg?


Takeoff performance includes the runway performance as well as the initial climb performance. For the initial climb performance there is a horizontal and vertical buffer surrounding the predicted flight path.

The performance software is saying that it is limited by an obstacle outside the airport that impinges this horizontal or vertical buffer.


But you don't have the runway performance chart stating which factor is limiting?
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 9:45 am

VSMUT wrote:
But you don't have the runway performance chart stating which factor is limiting?


No the A350 has no charts, it's all done via software. The software states the takeoff weight from 03L in JNB is limited by obstacles.

If you were to use charts for other aircraft it could give unrealistic regulated takeoff weights as it’s not taking into account the splay after liftoff.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 11:02 am

zeke wrote:
VSMUT wrote:
But you don't have the runway performance chart stating which factor is limiting?


No the A350 has no charts, it's all done via software. The software states the takeoff weight from 03L in JNB is limited by obstacles.


Lucky you. I still have to look it up on the iPad before departure. Great fun when they change the runway at the last moment.
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 11:07 am

VSMUT wrote:

Lucky you. I still have to look it up on the iPad before departure. Great fun when they change the runway at the last moment.


Have to look what up ? For what aircraft ?
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
VSMUT
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 11:09 am

zeke wrote:
VSMUT wrote:

Lucky you. I still have to look it up on the iPad before departure. Great fun when they change the runway at the last moment.


Have to look what up ? For what aircraft ?


The allowed MTOM and obstacle avoidance procedures (if applicable). On the ATR.
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 11:29 am

VSMUT wrote:
The allowed MTOM and obstacle avoidance procedures (if applicable). On the ATR.


Your airline could choose to use the iPad SPS software for the ATR which uses the same backend program (octopus) used on all of the Airbus aircraft, essentially the same as flysmart on the A350.

That way all environmental conditions, notams, obstacles, failures, and MELs can be taken account of accurately for any phase of flight.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
VSMUT
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 11:38 am

zeke wrote:
VSMUT wrote:
The allowed MTOM and obstacle avoidance procedures (if applicable). On the ATR.


Your airline could choose to use the iPad SPS software for the ATR which uses the same backend program (octopus) used on all of the Airbus aircraft, essentially the same as flysmart on the A350.

That way all environmental conditions, notams, obstacles, failures, and MELs can be taken account of accurately for any phase of flight.


It's all about the money €€€€€€€...
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 11:50 am

VSMUT wrote:

It's all about the money €€€€€€€...


With the more accurate performance more payload can be taken, plus reduced paperwork.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 12:31 pm

zeke wrote:
plus reduced paperwork.


Then how are all the beancounters going to justify their existance? :duck: No way, these guys want everything to be sent in 2 or 3 different forms with pretty much the same info on them, so they can "analyse the data for optimisation".
 
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zeke
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 14, 2020 1:07 pm

VSMUT wrote:

Then how are all the beancounters going to justify their existance? :duck: No way, these guys want everything to be sent in 2 or 3 different forms with pretty much the same info on them, so they can "analyse the data for optimisation".


The performance data is sent by email so a copy is retained just like they would with paper, without the need to have someone input the data from paper and then store the paper.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
jfk777
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 26, 2020 1:06 am

Delta could fly JFK to Johannesburg, New York doesn't have as many connections and more competition. From Atlanta they connect to 100 cities and have shown it can be done for a decade so why change what works ? USA to South Africa is a niche market, Delta has been the only airline recently flying there. Most connections are over Europe and a limited amount via Brazil.

United has the advantage of a large Newark hub next to New York, they should be able to make it work. Will they try something from Chicago or Washington in addition could be interesting.
 
FriscoHeavy
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sat Dec 26, 2020 3:47 am

jfk777 wrote:
Delta could fly JFK to Johannesburg, New York doesn't have as many connections and more competition. From Atlanta they connect to 100 cities and have shown it can be done for a decade so why change what works ? USA to South Africa is a niche market, Delta has been the only airline recently flying there. Most connections are over Europe and a limited amount via Brazil.

United has the advantage of a large Newark hub next to New York, they should be able to make it work. Will they try something from Chicago or Washington in addition could be interesting.


United does not have an aircraft that can make it from South Africa to Chicago.
Whatever
 
moyangmm
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sun Dec 27, 2020 7:43 pm

FriscoHeavy wrote:

United does not have an aircraft that can make it from South Africa to Chicago.


Yes it does: 787-9.

Meanwhile, it is a fact that Delta doesn't have the aircraft to fly nonstop from JNB to ATL.
 
DylanHarvey
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Sun Dec 27, 2020 7:57 pm

moyangmm wrote:
FriscoHeavy wrote:

United does not have an aircraft that can make it from South Africa to Chicago.


Yes it does: 787-9.

Meanwhile, it is a fact that Delta doesn't have the aircraft to fly nonstop from JNB to ATL.

I thought crack was an illegal drug? And yeah, with like 80 passengers you can fly a 789 that far.
 
FriscoHeavy
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Re: DL & UA on Johannesburg/JNB service aircraft performance (hot & high)

Mon Dec 28, 2020 2:54 am

moyangmm wrote:
FriscoHeavy wrote:

United does not have an aircraft that can make it from South Africa to Chicago.


Yes it does: 787-9.

Meanwhile, it is a fact that Delta doesn't have the aircraft to fly nonstop from JNB to ATL.


No, it doesn’t. ORD is about 700 miles (about an hour and a half) further than EWR. Unless they significantly weight restrict it (i.e. block seats), they can’t make it. Restricting that many seats would make the route uneconomical.

And I’m saying this as a HUGE 787 fan (much more so than the A350).
Whatever

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