Should I switch the transponder to STBY or not while changing codes?
up vote
6
down vote
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I´m now reading Bob Gardner’s book “Say again, please” and there is this instruction on page 54: “Do not turn the transponder function switch to STBY while changing codes.”
What is the reason for this? I’m a PPL student and my instructor told me the opposite.
transponder
edited 48 mins ago
Pondlife
50k8134274
asked 5 hours ago
Hask Somatotoian
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Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
up vote
6
down vote
favorite
I´m now reading Bob Gardner’s book “Say again, please” and there is this instruction on page 54: “Do not turn the transponder function switch to STBY while changing codes.”
What is the reason for this? I’m a PPL student and my instructor told me the opposite.
transponder
edited 48 mins ago
Pondlife
50k8134274
asked 5 hours ago
Hask Somatotoian
311
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
up vote
6
down vote
favorite
up vote
6
down vote
favorite
I´m now reading Bob Gardner’s book “Say again, please” and there is this instruction on page 54: “Do not turn the transponder function switch to STBY while changing codes.”
What is the reason for this? I’m a PPL student and my instructor told me the opposite.
transponder
edited 48 mins ago
Pondlife
50k8134274
asked 5 hours ago
Hask Somatotoian
311
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I´m now reading Bob Gardner’s book “Say again, please” and there is this instruction on page 54: “Do not turn the transponder function switch to STBY while changing codes.”
What is the reason for this? I’m a PPL student and my instructor told me the opposite.
transponder
transponder
edited 48 mins ago
Pondlife
50k8134274
asked 5 hours ago
Hask Somatotoian
311
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 48 mins ago
Pondlife
50k8134274
asked 5 hours ago
Hask Somatotoian
311
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 48 mins ago
Pondlife
50k8134274
edited 48 mins ago
Pondlife
50k8134274
edited 48 mins ago
Pondlife
50k8134274
50k8134274
asked 5 hours ago
Hask Somatotoian
311
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 5 hours ago
Hask Somatotoian
311
asked 5 hours ago
Hask Somatotoian
311
311
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Hask Somatotoian is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
up vote
8
down vote
The FAA started advocating not selecting standby for code changes after it was found that more often than one would expect, the transponder doesn't always come back on after standby. Seems they uncovered a number of switch failures.
I figure that someone decided that for TCAS it was better to have a transponder squawking any code than not squawking. But that is my own conjecture.
So for quite a few years the guidance has been to not turn to standby when selecting codes.
I have had the folks at Flight Safety lecture me after sim sessions, with pretty much the same story.
So I now teach students to just switch the codes, and not standby the transponder. And I suggest caution when dialing through "7xxx" although controllers I have talked to say it's not a big deal.
So the idea is to keep the transponder squawking, even though numbers are being changed. There is continuity in that they will continue to have returns while you are playing with the knobs. And if you ever have a switch failure, it will likely be on the ground.
Addendum: Also, with ADS-B, one is supposed to keep the transponder on at all times, when on the airport surface in a movement area. So I can see that the philosophy of managing the standby position will continue to change.
answered 3 hours ago
mongo
11.2k1051
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
add a comment |
up vote
3
down vote
The AIM implies that you should leave the transponder on ALT when changing codes—since if you are in standby you won’t be transmitting:
4−1−20. Transponder Operation
e. Code Changes
- When making routine code changes, pilots should avoid inadvertent selection of Codes 7500, 7600 or 7700 thereby causing momentary false
alarms at automated ground facilities. For example, when switching
from Code 2700 to Code 7200, switch first to 2200 then to 7200, NOT to
7700 and then 7200. This procedure applies to nondiscrete Code 7500
and all discrete codes in the 7600 and 7700 series (i.e., 7600−7677,
7700−7777) which will trigger special indicators in automated
facilities. Only nondiscrete Code 7500 will be decoded as the hijack
code.
answered 3 hours ago
JScarry
3,7541623
add a comment |
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
8
down vote
The FAA started advocating not selecting standby for code changes after it was found that more often than one would expect, the transponder doesn't always come back on after standby. Seems they uncovered a number of switch failures.
I figure that someone decided that for TCAS it was better to have a transponder squawking any code than not squawking. But that is my own conjecture.
So for quite a few years the guidance has been to not turn to standby when selecting codes.
I have had the folks at Flight Safety lecture me after sim sessions, with pretty much the same story.
So I now teach students to just switch the codes, and not standby the transponder. And I suggest caution when dialing through "7xxx" although controllers I have talked to say it's not a big deal.
So the idea is to keep the transponder squawking, even though numbers are being changed. There is continuity in that they will continue to have returns while you are playing with the knobs. And if you ever have a switch failure, it will likely be on the ground.
Addendum: Also, with ADS-B, one is supposed to keep the transponder on at all times, when on the airport surface in a movement area. So I can see that the philosophy of managing the standby position will continue to change.
answered 3 hours ago
mongo
11.2k1051
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
add a comment |
up vote
8
down vote
The FAA started advocating not selecting standby for code changes after it was found that more often than one would expect, the transponder doesn't always come back on after standby. Seems they uncovered a number of switch failures.
I figure that someone decided that for TCAS it was better to have a transponder squawking any code than not squawking. But that is my own conjecture.
So for quite a few years the guidance has been to not turn to standby when selecting codes.
I have had the folks at Flight Safety lecture me after sim sessions, with pretty much the same story.
So I now teach students to just switch the codes, and not standby the transponder. And I suggest caution when dialing through "7xxx" although controllers I have talked to say it's not a big deal.
So the idea is to keep the transponder squawking, even though numbers are being changed. There is continuity in that they will continue to have returns while you are playing with the knobs. And if you ever have a switch failure, it will likely be on the ground.
Addendum: Also, with ADS-B, one is supposed to keep the transponder on at all times, when on the airport surface in a movement area. So I can see that the philosophy of managing the standby position will continue to change.
answered 3 hours ago
mongo
11.2k1051
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
add a comment |
up vote
8
down vote
up vote
8
down vote
The FAA started advocating not selecting standby for code changes after it was found that more often than one would expect, the transponder doesn't always come back on after standby. Seems they uncovered a number of switch failures.
I figure that someone decided that for TCAS it was better to have a transponder squawking any code than not squawking. But that is my own conjecture.
So for quite a few years the guidance has been to not turn to standby when selecting codes.
I have had the folks at Flight Safety lecture me after sim sessions, with pretty much the same story.
So I now teach students to just switch the codes, and not standby the transponder. And I suggest caution when dialing through "7xxx" although controllers I have talked to say it's not a big deal.
So the idea is to keep the transponder squawking, even though numbers are being changed. There is continuity in that they will continue to have returns while you are playing with the knobs. And if you ever have a switch failure, it will likely be on the ground.
Addendum: Also, with ADS-B, one is supposed to keep the transponder on at all times, when on the airport surface in a movement area. So I can see that the philosophy of managing the standby position will continue to change.
answered 3 hours ago
mongo
11.2k1051
The FAA started advocating not selecting standby for code changes after it was found that more often than one would expect, the transponder doesn't always come back on after standby. Seems they uncovered a number of switch failures.
I figure that someone decided that for TCAS it was better to have a transponder squawking any code than not squawking. But that is my own conjecture.
So for quite a few years the guidance has been to not turn to standby when selecting codes.
I have had the folks at Flight Safety lecture me after sim sessions, with pretty much the same story.
So I now teach students to just switch the codes, and not standby the transponder. And I suggest caution when dialing through "7xxx" although controllers I have talked to say it's not a big deal.
So the idea is to keep the transponder squawking, even though numbers are being changed. There is continuity in that they will continue to have returns while you are playing with the knobs. And if you ever have a switch failure, it will likely be on the ground.
Addendum: Also, with ADS-B, one is supposed to keep the transponder on at all times, when on the airport surface in a movement area. So I can see that the philosophy of managing the standby position will continue to change.
answered 3 hours ago
mongo
11.2k1051
edited 48 mins ago
answered 3 hours ago
mongo
11.2k1051
answered 3 hours ago
mongo
11.2k1051
answered 3 hours ago
mongo
11.2k1051
11.2k1051
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
add a comment |
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Also, it is probably more likely for it to be "pilot error" than "switch failure" when the transponder doesn't come back on after setting the code....
– Lnafziger
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
Modern electronically controlled transponders have a delay that waits until a few seconds after dialing stops before committing the change. And a lot of them are keypad entry now, which avoids the problem too.
– user71659
2 hours ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
For a while I would fly a plane daily which would not do the 0400 bit, and of course the local TRACON assigned 0400 bit codes. The unit would go to the shop, get certified and then the switch(i assume) would get spotty. I would negotiate another code with ATC. The only people who were really annoyed were the NYC TRACON folks. Then again, at one time, I flew equipment which had two digit transponders. Yep, 12 for VFR.
– mongo
53 mins ago
add a comment |
up vote
3
down vote
The AIM implies that you should leave the transponder on ALT when changing codes—since if you are in standby you won’t be transmitting:
4−1−20. Transponder Operation
e. Code Changes
- When making routine code changes, pilots should avoid inadvertent selection of Codes 7500, 7600 or 7700 thereby causing momentary false
alarms at automated ground facilities. For example, when switching
from Code 2700 to Code 7200, switch first to 2200 then to 7200, NOT to
7700 and then 7200. This procedure applies to nondiscrete Code 7500
and all discrete codes in the 7600 and 7700 series (i.e., 7600−7677,
7700−7777) which will trigger special indicators in automated
facilities. Only nondiscrete Code 7500 will be decoded as the hijack
code.
answered 3 hours ago
JScarry
3,7541623
add a comment |
up vote
3
down vote
The AIM implies that you should leave the transponder on ALT when changing codes—since if you are in standby you won’t be transmitting:
4−1−20. Transponder Operation
e. Code Changes
- When making routine code changes, pilots should avoid inadvertent selection of Codes 7500, 7600 or 7700 thereby causing momentary false
alarms at automated ground facilities. For example, when switching
from Code 2700 to Code 7200, switch first to 2200 then to 7200, NOT to
7700 and then 7200. This procedure applies to nondiscrete Code 7500
and all discrete codes in the 7600 and 7700 series (i.e., 7600−7677,
7700−7777) which will trigger special indicators in automated
facilities. Only nondiscrete Code 7500 will be decoded as the hijack
code.
answered 3 hours ago
JScarry
3,7541623
add a comment |
up vote
3
down vote
up vote
3
down vote
The AIM implies that you should leave the transponder on ALT when changing codes—since if you are in standby you won’t be transmitting:
4−1−20. Transponder Operation
e. Code Changes
- When making routine code changes, pilots should avoid inadvertent selection of Codes 7500, 7600 or 7700 thereby causing momentary false
alarms at automated ground facilities. For example, when switching
from Code 2700 to Code 7200, switch first to 2200 then to 7200, NOT to
7700 and then 7200. This procedure applies to nondiscrete Code 7500
and all discrete codes in the 7600 and 7700 series (i.e., 7600−7677,
7700−7777) which will trigger special indicators in automated
facilities. Only nondiscrete Code 7500 will be decoded as the hijack
code.
answered 3 hours ago
JScarry
3,7541623
The AIM implies that you should leave the transponder on ALT when changing codes—since if you are in standby you won’t be transmitting:
4−1−20. Transponder Operation
e. Code Changes
- When making routine code changes, pilots should avoid inadvertent selection of Codes 7500, 7600 or 7700 thereby causing momentary false
alarms at automated ground facilities. For example, when switching
from Code 2700 to Code 7200, switch first to 2200 then to 7200, NOT to
7700 and then 7200. This procedure applies to nondiscrete Code 7500
and all discrete codes in the 7600 and 7700 series (i.e., 7600−7677,
7700−7777) which will trigger special indicators in automated
facilities. Only nondiscrete Code 7500 will be decoded as the hijack
code.
answered 3 hours ago
JScarry
3,7541623
answered 3 hours ago
JScarry
3,7541623
answered 3 hours ago
JScarry
3,7541623
answered 3 hours ago
JScarry
3,7541623
3,7541623
add a comment |
add a comment |
Hask Somatotoian is a new contributor. Be nice, and check out our Code of Conduct.
Hask Somatotoian is a new contributor. Be nice, and check out our Code of Conduct.
Hask Somatotoian is a new contributor. Be nice, and check out our Code of Conduct.
Hask Somatotoian is a new contributor. Be nice, and check out our Code of Conduct.
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