Airbus 320 single-engine taxi-out
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Airbus 320 single-engine taxi-out
A few questions for all those who routinely use single-engine taxi-out on the A320 series:
1) Do you have company/tailored SOPs for this?
1a) If you use basic Airbus manuals, is there any company guidance on how to apply them, especially regarding task sharing?
2) Is the second engine start done read & do, from memory or something in between/different?
3) Is the pilot taxiing the aircraft involved in the procedure other than ordering the engine start and if so, how?
I would appreciate if you could identify your operator or at least the continent and kind of ops.
Thanks!
(Background: trying to champion it here against unexpectedly fierce opposition.)
1) Do you have company/tailored SOPs for this?
1a) If you use basic Airbus manuals, is there any company guidance on how to apply them, especially regarding task sharing?
2) Is the second engine start done read & do, from memory or something in between/different?
3) Is the pilot taxiing the aircraft involved in the procedure other than ordering the engine start and if so, how?
I would appreciate if you could identify your operator or at least the continent and kind of ops.
Thanks!
(Background: trying to champion it here against unexpectedly fierce opposition.)
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It’s in the standard ops for us:
PF: start engine 2
PM: (as a flow and verbalizing the actions)
Y elec Pump off
APU bleed on
eng mode selec: IGN/Start
….. check pressure is ok to avoid eng stall and ENG 2 start
start up completed as a flow eng mode selec normal, apu bleed off, (eai 2 on if needed) and apu master off.
after start cklist
PF: start engine 2
PM: (as a flow and verbalizing the actions)
Y elec Pump off
APU bleed on
eng mode selec: IGN/Start
….. check pressure is ok to avoid eng stall and ENG 2 start
start up completed as a flow eng mode selec normal, apu bleed off, (eai 2 on if needed) and apu master off.
after start cklist
Standard ops for us too. Read and do from the QRH by PM with a cross check of the correct engine master by PF. Both the before start and after start procedures are in the QRH so no after start checklist for us.
European airline, 100+ shorthaul Airbus.
European airline, 100+ shorthaul Airbus.
Last edited by Locked door; 7th Apr 2024 at 14:47.
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We routinely taxi both single-engine taxi-out/in. This obviously depending on taxiway state (not a good idea when slippery or need for periodic runup etc.) It also depends on how long to taxi / unfamiliar airport, complex taxiing etc. In other words, use your head as to whether it makes tactical sense.
1, We have SOP either to perform start of engine no 2 by heart, or by support items on the normal checklist or in the eQRH. How to is the individual pilots choice.
2, PF focuses on taxi, PF determines when to start no 2 and says "start engine no2". PM (speaking out loud) Yellow elec pump off /APU bleed on/ engine mode select ignition / when bleed psi sufficient: no2 master lever on. When engine no 2 started and stable, PM turns off APU bleed+ APU, then mode select normal (eng.2 antiice if needed) and calls out loud: "engine start procedure completed". We have a hard rule that the after start checklist MUST be completed before initiating taxi, either 1- or 2-engine taxi (reason being after start checklist includes killer items such as clear signal etc form ground staff/ tug removed etc).
3, Obviously, PF is focusing on the AVIATE part (maneuvering the aircraft safely), but at the same time, follows along with what PM is verbalising.
Training Captain with SAS (Northern Europe)
1, We have SOP either to perform start of engine no 2 by heart, or by support items on the normal checklist or in the eQRH. How to is the individual pilots choice.
2, PF focuses on taxi, PF determines when to start no 2 and says "start engine no2". PM (speaking out loud) Yellow elec pump off /APU bleed on/ engine mode select ignition / when bleed psi sufficient: no2 master lever on. When engine no 2 started and stable, PM turns off APU bleed+ APU, then mode select normal (eng.2 antiice if needed) and calls out loud: "engine start procedure completed". We have a hard rule that the after start checklist MUST be completed before initiating taxi, either 1- or 2-engine taxi (reason being after start checklist includes killer items such as clear signal etc form ground staff/ tug removed etc).
3, Obviously, PF is focusing on the AVIATE part (maneuvering the aircraft safely), but at the same time, follows along with what PM is verbalising.
Training Captain with SAS (Northern Europe)
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We do as above and it's rarely worth it at most of the airports we fly to. Even the major international ones tbh. Saves a minute or two at best for an incredible addition to workload. The only place it's worth it is Amsterdam or Barcelona because of where we park.
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If you think that starting an engine whilst taxying is an incredible amount of workload, then I understand why you think it’s not worth it on most airports. Single engine taxi is the default in our manual. And also in my own personal preference: start one engine unless…
The more you do it, the less of a perceived additional workload it becomes.
The more you do it, the less of a perceived additional workload it becomes.
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A few questions for all those who routinely use single-engine taxi-out on the A320 series:
1) Do you have company/tailored SOPs for this?
1a) If you use basic Airbus manuals, is there any company guidance on how to apply them, especially regarding task sharing?
2) Is the second engine start done read & do, from memory or something in between/different?
3) Is the pilot taxiing the aircraft involved in the procedure other than ordering the engine start and if so, how?
I would appreciate if you could identify your operator or at least the continent and kind of ops.
Thanks!
(Background: trying to champion it here against unexpectedly fierce opposition.)
1) Do you have company/tailored SOPs for this?
1a) If you use basic Airbus manuals, is there any company guidance on how to apply them, especially regarding task sharing?
2) Is the second engine start done read & do, from memory or something in between/different?
3) Is the pilot taxiing the aircraft involved in the procedure other than ordering the engine start and if so, how?
I would appreciate if you could identify your operator or at least the continent and kind of ops.
Thanks!
(Background: trying to champion it here against unexpectedly fierce opposition.)
1) Yes. both SETO and SETI done fully by memory. The only exception is the “after engine 2 start” where the PM reads and does the action (I.e.chrono start, mode sel NORM, Apu bleed off, Apu off) and then we go to the after start checklist.
90+% of our taxi are SETI/SETO, even for just 30 seconds.
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They are, but assume that systems are configured for start. Once you start taxying the bleed needs reconfiguring as well as the hydraulics (which you supplement with an electric pump during single engine taxi but that should come off prior to engine start) - See I-WEBA's post..
It’s almost always worth SETO unless you’re constrained by engine warm up time, and as previous posters have pointed out if you practice it it’s not difficult.
Even if you only save 50kg, 50kg saved on a sector is 100kg on two sectors. If you’re a medium size airline multiply that by 200 “there and backs” a day is 20000kg a day, multiplied by 365 is 7,300,000 kg saved per year. That roughly equates to $7.3 million in reduced fuel costs per year and 65700 fewer tonnes of CO2 in the atmosphere.
On an individual level any fuel saved on taxi out remains available for use later in the sector. That extra 200kg fuel saved might just be the difference between holding longer or making a second approach and getting in rather than diverting from destination.
Marginal gains make a big difference when multiplied.
I often start the second engine almost immediately after commencing taxi if it’s a short taxi. That reduces eng 1 run time as you’re moving during eng 2 start (assuming no atc delay prior to departure) and saves a small amount of fuel. Over a career that will be a very large amount of fuel saved.
LD
Even if you only save 50kg, 50kg saved on a sector is 100kg on two sectors. If you’re a medium size airline multiply that by 200 “there and backs” a day is 20000kg a day, multiplied by 365 is 7,300,000 kg saved per year. That roughly equates to $7.3 million in reduced fuel costs per year and 65700 fewer tonnes of CO2 in the atmosphere.
On an individual level any fuel saved on taxi out remains available for use later in the sector. That extra 200kg fuel saved might just be the difference between holding longer or making a second approach and getting in rather than diverting from destination.
Marginal gains make a big difference when multiplied.
I often start the second engine almost immediately after commencing taxi if it’s a short taxi. That reduces eng 1 run time as you’re moving during eng 2 start (assuming no atc delay prior to departure) and saves a small amount of fuel. Over a career that will be a very large amount of fuel saved.
LD
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It’s almost always worth SETO unless you’re constrained by engine warm up time, and as previous posters have pointed out if you practice it it’s not difficult.
Even if you only save 50kg, 50kg saved on a sector is 100kg on two sectors. If you’re a medium size airline multiply that by 200 “there and backs” a day is 20000kg a day, multiplied by 365 is 7,300,000 kg saved per year. That roughly equates to $7.3 million in reduced fuel costs per year and 65700 fewer tonnes of CO2 in the atmosphere.
On an individual level any fuel saved on taxi out remains available for use later in the sector. That extra 200kg fuel saved might just be the difference between holding longer or making a second approach and getting in rather than diverting from destination.
Marginal gains make a big difference when multiplied.
I often start the second engine almost immediately after commencing taxi if it’s a short taxi. That reduces eng 1 run time as you’re moving during eng 2 start (assuming no atc delay prior to departure) and saves a small amount of fuel. Over a career that will be a very large amount of fuel saved.
LD
Even if you only save 50kg, 50kg saved on a sector is 100kg on two sectors. If you’re a medium size airline multiply that by 200 “there and backs” a day is 20000kg a day, multiplied by 365 is 7,300,000 kg saved per year. That roughly equates to $7.3 million in reduced fuel costs per year and 65700 fewer tonnes of CO2 in the atmosphere.
On an individual level any fuel saved on taxi out remains available for use later in the sector. That extra 200kg fuel saved might just be the difference between holding longer or making a second approach and getting in rather than diverting from destination.
Marginal gains make a big difference when multiplied.
I often start the second engine almost immediately after commencing taxi if it’s a short taxi. That reduces eng 1 run time as you’re moving during eng 2 start (assuming no atc delay prior to departure) and saves a small amount of fuel. Over a career that will be a very large amount of fuel saved.
LD
Also for those airlines (like mine) that have embodied the SETO/SETI into their normal OPS flow (I.e. done by memory) there’s virtually almost no increase in workload.
We use basic Airbus manuals. We are allowed to do this procedure from memory, which does not pose many problems in itself.
The PF is not involved in the startup.
Airline is european mainline with 100+ airbuses at this time.
However I'm going to contradict many people here : the gain is not huge.
Being an F/O, I always followed the CP's opinion regarding SETO. I do not care personnally about doing it or not, it's not directly out of or in my pocket. So I had plenty of opportunities to work both with captains who loved to do it, and others who never did it.
To me, dual engine taxi out works like insurance. You may pay a little bit more at each leg (however we'll see about that) but you will pay a lot whenever problems will arise. And it balances out. You may save a few bucks over thousands of flights, but you will lose them all when the procedure is mis-applied and leads to an incident, and flight cancellation.
So why doesn't save as much as we can think ? SETO has a slower taxi speed. I've seen people say on some occasions that SETO is doable even on very short taxi routes. And to have enough time to start up the second engine, warm it up and do all the procedures, they will taxi even slower.
So let's be clear. Having the APU on and one engine burns the same fuel per kilometer taxied at 20kt, than having two engines, no APU, and taxiing at 30kt. It turns out that these are typical speeds that are reached in single engine and dual engine taxi. So fuel consumption may be close to equivalent.
However costs might be slightly smaller since you're reducing engine time on the shut off engine. Yes.
I still feel like it goes against flight safety, and efficiency of the flight. If you're having a high workload while taxing, starting engines, running through flows and checklists, a lot of talking, there is a higher chance of missing important trafic information going on on the frequency. On several occasions, a too talkative colleague made us miss important radio calls from other planes directly conflicting with us.
It also goes against flight safety to be starting engines while taxiing. All possible errors have been made or will be made. Taxiway excursion. Shutting down the live engine. Even takeoff attempt on single engine. That's without talking about the before takeoff procedures which may be easily shortened due to time pressure.
To finish with, I had one example which finished to convince me against it. One time, first flight of the day, we were performing a single engine taxi out and had a failure while starting the second engine. Some mechanical part was broken.
We took one hour just to find a new parking spot. Had we been just in front of our gate, we would have had our own parking spot back for ourselves. We ended up with a distant parking, everything about the repair and second departure to our destination was made more complicated.
I doubt I performed enough SETO, in the entire rest of my carreer on this plane, to compensate just for all the missed connections on that day (all of them for the entire day)
If fuel price triples and on airplanes allowed to single engine taxi without the APU, it may become a sound choice.
The PF is not involved in the startup.
Airline is european mainline with 100+ airbuses at this time.
However I'm going to contradict many people here : the gain is not huge.
Being an F/O, I always followed the CP's opinion regarding SETO. I do not care personnally about doing it or not, it's not directly out of or in my pocket. So I had plenty of opportunities to work both with captains who loved to do it, and others who never did it.
To me, dual engine taxi out works like insurance. You may pay a little bit more at each leg (however we'll see about that) but you will pay a lot whenever problems will arise. And it balances out. You may save a few bucks over thousands of flights, but you will lose them all when the procedure is mis-applied and leads to an incident, and flight cancellation.
So why doesn't save as much as we can think ? SETO has a slower taxi speed. I've seen people say on some occasions that SETO is doable even on very short taxi routes. And to have enough time to start up the second engine, warm it up and do all the procedures, they will taxi even slower.
So let's be clear. Having the APU on and one engine burns the same fuel per kilometer taxied at 20kt, than having two engines, no APU, and taxiing at 30kt. It turns out that these are typical speeds that are reached in single engine and dual engine taxi. So fuel consumption may be close to equivalent.
However costs might be slightly smaller since you're reducing engine time on the shut off engine. Yes.
I still feel like it goes against flight safety, and efficiency of the flight. If you're having a high workload while taxing, starting engines, running through flows and checklists, a lot of talking, there is a higher chance of missing important trafic information going on on the frequency. On several occasions, a too talkative colleague made us miss important radio calls from other planes directly conflicting with us.
It also goes against flight safety to be starting engines while taxiing. All possible errors have been made or will be made. Taxiway excursion. Shutting down the live engine. Even takeoff attempt on single engine. That's without talking about the before takeoff procedures which may be easily shortened due to time pressure.
To finish with, I had one example which finished to convince me against it. One time, first flight of the day, we were performing a single engine taxi out and had a failure while starting the second engine. Some mechanical part was broken.
We took one hour just to find a new parking spot. Had we been just in front of our gate, we would have had our own parking spot back for ourselves. We ended up with a distant parking, everything about the repair and second departure to our destination was made more complicated.
I doubt I performed enough SETO, in the entire rest of my carreer on this plane, to compensate just for all the missed connections on that day (all of them for the entire day)
If fuel price triples and on airplanes allowed to single engine taxi without the APU, it may become a sound choice.
To answer the above post
1. Taxi speed on one engine is the same as on two engines.
2. If you have to slow down to accommodate the 2nd engine start you’re starting it too late.
3. Even if you do slow down by 10 knots 1 eng + APU is still a significant saving over two engines unless you have a LEAP1A strapped to the tail.
4. Part of your pre flight briefing should be to identify the best place to start the 2nd engine for fuel saving vs workload.
5. If your worried about shutting down instead of starting or an excursion or other mistakes, up the rigour level.
6. In your start failure example those passengers would have missed all their connections anyway, SETO or not. Most busy airports won’t put you back on the same stand after push as it will already have been allocated and you aren’t fixing the engine quickly.
7. Even if in that example SETO did cause you to burn an hours fuel, if you do 5 mins SETO on subsequent sectors you’ll make that fuel up in 12 flights. That’s less than a week.
As I said right at the start of this thread, SETO intelligently applied poses no safety risk and enhances safety by increasing the amount of the available fuel during the flight. It also has cost and environmental benefits. Those that don’t want to do it will always find excuses which don’t actually stand up to scrutiny (same as for flap three landings).
Anyone can fly around with their mind in neutral and will find ways to justify their behaviour. Operating efficiently requires thought and effort but there are safety, cost and environmental rewards.
We’re not talking about timing the second start to the millisecond, just delay it as long as is reasonably practicable.
ATB
LD
1. Taxi speed on one engine is the same as on two engines.
2. If you have to slow down to accommodate the 2nd engine start you’re starting it too late.
3. Even if you do slow down by 10 knots 1 eng + APU is still a significant saving over two engines unless you have a LEAP1A strapped to the tail.
4. Part of your pre flight briefing should be to identify the best place to start the 2nd engine for fuel saving vs workload.
5. If your worried about shutting down instead of starting or an excursion or other mistakes, up the rigour level.
6. In your start failure example those passengers would have missed all their connections anyway, SETO or not. Most busy airports won’t put you back on the same stand after push as it will already have been allocated and you aren’t fixing the engine quickly.
7. Even if in that example SETO did cause you to burn an hours fuel, if you do 5 mins SETO on subsequent sectors you’ll make that fuel up in 12 flights. That’s less than a week.
As I said right at the start of this thread, SETO intelligently applied poses no safety risk and enhances safety by increasing the amount of the available fuel during the flight. It also has cost and environmental benefits. Those that don’t want to do it will always find excuses which don’t actually stand up to scrutiny (same as for flap three landings).
Anyone can fly around with their mind in neutral and will find ways to justify their behaviour. Operating efficiently requires thought and effort but there are safety, cost and environmental rewards.
We’re not talking about timing the second start to the millisecond, just delay it as long as is reasonably practicable.
ATB
LD
Last edited by Locked door; 10th Apr 2024 at 18:05.
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On a similar note: Is single engine taxi out on the 737 used as much? From what I understand, starting an engine on a 737 is much more complicated thanks to the vintage design.
It’s not quite as simple as this though in determining the fuel savings. On a heavier A320 you will have to considerably increase the thrust used on one engine to get the aircraft moving and burn potentially more fuel using just that one engine than if you had started both initially. Once you get going though and have the inertia it becomes an effective fuel saving initiative. Depending on the taxi routing I.e 90deg turns and reduction in speed required to navigate as such, especially at higher weights again the above is true. It’s not just a simple 50/50 saving.
As I said right at the start of this thread, SETO intelligently applied poses no safety risk and enhances safety by increasing the amount of the available fuel during the flight. It also has cost and environmental benefits. Those that don’t want to do it will always find excuses which don’t actually stand up to scrutiny (same as for flap three landings).
ATB
LD
ATB
LD
But this one is quite a marvel.
SETO enhances safety. That is creative. Thank you for writing it.
The fuel saving is minimal. It can equate to around one minute of extra time.
On the other hand the increase in workload proved to cause safety problems during operations, many times.
You can read this thread :
A320 single engine taxi out threats
"Our company just had a runway incursion as a direct result"
Another example incident here :
https://aviationweek.com/air-transpo...against-safety
Many other happened including some at our airline, nobody's perfect.
The threats include runway incursion, taxiway excursion (you're moving at 20kt with an incomplete aircraft), taxiway conflicts, including due to missed radio calls, higher workload preventing you from accepting a better runway, or managing any other specificity on that taxi out, mismanaging the procedure itself, etc.. That's without talking about passenger comfort and the noisy yellow pump, and punctuality.
To answer the above post
1. Taxi speed on one engine is the same as on two engines.
2. If you have to slow down to accommodate the 2nd engine start you’re starting it too late.
3. Even if you do slow down by 10 knots 1 eng + APU is still a significant saving over two engines unless you have a LEAP1A strapped to the tail.
4. Part of your pre flight briefing should be to identify the best place to start the 2nd engine for fuel saving vs workload.
5. If your worried about shutting down instead of starting or an excursion or other mistakes, up the rigour level.
6. In your start failure example those passengers would have missed all their connections anyway, SETO or not. Most busy airports won’t put you back on the same stand after push as it will already have been allocated and you aren’t fixing the engine quickly.
7. Even if in that example SETO did cause you to burn an hours fuel, if you do 5 mins SETO on subsequent sectors you’ll make that fuel up in 12 flights. That’s less than a week.
As I said right at the start of this thread, SETO intelligently applied poses no safety risk and enhances safety by increasing the amount of the available fuel during the flight. It also has cost and environmental benefits. Those that don’t want to do it will always find excuses which don’t actually stand up to scrutiny (same as for flap three landings).
Anyone can fly around with their mind in neutral and will find ways to justify their behaviour. Operating efficiently requires thought and effort but there are safety, cost and environmental rewards.
We’re not talking about timing the second start to the millisecond, just delay it as long as is reasonably practicable.
ATB
LD
1. Taxi speed on one engine is the same as on two engines.
2. If you have to slow down to accommodate the 2nd engine start you’re starting it too late.
3. Even if you do slow down by 10 knots 1 eng + APU is still a significant saving over two engines unless you have a LEAP1A strapped to the tail.
4. Part of your pre flight briefing should be to identify the best place to start the 2nd engine for fuel saving vs workload.
5. If your worried about shutting down instead of starting or an excursion or other mistakes, up the rigour level.
6. In your start failure example those passengers would have missed all their connections anyway, SETO or not. Most busy airports won’t put you back on the same stand after push as it will already have been allocated and you aren’t fixing the engine quickly.
7. Even if in that example SETO did cause you to burn an hours fuel, if you do 5 mins SETO on subsequent sectors you’ll make that fuel up in 12 flights. That’s less than a week.
As I said right at the start of this thread, SETO intelligently applied poses no safety risk and enhances safety by increasing the amount of the available fuel during the flight. It also has cost and environmental benefits. Those that don’t want to do it will always find excuses which don’t actually stand up to scrutiny (same as for flap three landings).
Anyone can fly around with their mind in neutral and will find ways to justify their behaviour. Operating efficiently requires thought and effort but there are safety, cost and environmental rewards.
We’re not talking about timing the second start to the millisecond, just delay it as long as is reasonably practicable.
ATB
LD
Fuel savings SETO? Unless there is a significant delay, I’d say the fuel saving would be negligible.
We get quarterly fuel saving statistics produced from FDR data, I can’t post the document here as it’s commercially sensitive but I can tell you in the last quarter I saved 3.2 tonnes single engine taxi out, 1.9 tonnes taxi in. The fleet saved over 900 tonnes SETO and over 800 tonnes SETI in the same period. That’s just three months.
That is not insignificant.
That is not insignificant.
Last edited by Locked door; 11th Apr 2024 at 15:21.
How is this calculated ?
Many instructors show the fuel consumption on the live side and say "that's how much we saved". It's plain wrong.
My understanding was that the real explanation for one engine taxi was to save on engine time, hence on maintenance costs.
Many instructors show the fuel consumption on the live side and say "that's how much we saved". It's plain wrong.
My understanding was that the real explanation for one engine taxi was to save on engine time, hence on maintenance costs.
There are many advantages to SETO as I’ve said before.
Reduced engine run time (especially useful for “power by the hour” leasing contracts).
More fuel available at destination (the safety advantage you scoffed at). Twice in my career I’ve ended up with less fuel at destination than I wanted with everything looking fine at ToD, both times I was very happy to have the extra 100-200kg I’d saved on the ground on departure.
Cooler brakes at places like EDDS and EDDF.
And reduced fuel costs and environmental benefit.
Our data is produced by knowing the average fuel burn for the time from first movement to setting T/O power for a two engine taxi and subtracting the actual fuel used by both engines and APU burn. It’s pretty accurate.
Your point about the fuel saving not being just the difference between eng 1 and eng 2 burn at the start of the take off roll is noted and correct but the saving is still significant and our data is cleverer than that.
It’s not always appropriate to perform SETO. It’s prohibited for us with contamination and some MEL’s. For workload management I start early before crossing runways (eg LEBL).
We perform the after start checklist as normal for both one and two engine taxi, then start no. 2 using read and do from the QRH, no memory actions.
The QRH also contains extra info like checking the accumulator pressure prior to push as it won’t be supplied until the y elec pump goes on as part of the after start flow to ensure brakes are available in case of tow bar separation in the push. Also turn no corners between y elec pump off and five secs after eng 2 master on as the yellow system could be unpowered potentially causing temporary loss of the NWS.
This job is all about risk / reward management. Done with thought SETO rewards far outweigh any small increase in risk.
ATB
LD
Reduced engine run time (especially useful for “power by the hour” leasing contracts).
More fuel available at destination (the safety advantage you scoffed at). Twice in my career I’ve ended up with less fuel at destination than I wanted with everything looking fine at ToD, both times I was very happy to have the extra 100-200kg I’d saved on the ground on departure.
Cooler brakes at places like EDDS and EDDF.
And reduced fuel costs and environmental benefit.
Our data is produced by knowing the average fuel burn for the time from first movement to setting T/O power for a two engine taxi and subtracting the actual fuel used by both engines and APU burn. It’s pretty accurate.
Your point about the fuel saving not being just the difference between eng 1 and eng 2 burn at the start of the take off roll is noted and correct but the saving is still significant and our data is cleverer than that.
It’s not always appropriate to perform SETO. It’s prohibited for us with contamination and some MEL’s. For workload management I start early before crossing runways (eg LEBL).
We perform the after start checklist as normal for both one and two engine taxi, then start no. 2 using read and do from the QRH, no memory actions.
The QRH also contains extra info like checking the accumulator pressure prior to push as it won’t be supplied until the y elec pump goes on as part of the after start flow to ensure brakes are available in case of tow bar separation in the push. Also turn no corners between y elec pump off and five secs after eng 2 master on as the yellow system could be unpowered potentially causing temporary loss of the NWS.
This job is all about risk / reward management. Done with thought SETO rewards far outweigh any small increase in risk.
ATB
LD
Last edited by Locked door; 11th Apr 2024 at 15:18.