Transponder code with an 8 or 9

EdFred said:
14CFR91.215(b)

"...aircraft is equipped with an operable coded radar beacon transponder having either Mode 3/A 4096 code capability..."

Never crossed anyone's mind that 4096 doesn't divide evenly by 10 (digits 0-9) ?
Never noticed it's a power of 8 (digits 0-7) ?
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Everyone with a degree in computer science did. But probably nobody else.
 
Why would it matter whether anyone understands octal or not? ATC gives you a code; you enter said code. What is the problem with the fact that they don;t issue you a code that starts with 8 or 9.

It is more important to know that if you receive a code that starts with "0" or "1" that you will probably have to reset it if you are on a x-country. But even that isn't important to know because ATC will tell you to reset your code and you will reset the code. Who cares "why".
 
JOhnH said:
Why would it matter whether anyone understands octal or not? ATC gives you a code; you enter said code. What is the problem with the fact that they don;t issue you a code that starts with 8 or 9.

It is more important to know that if you receive a code that starts with "0" or "1" that you will probably have to reset it if you are on a x-country. But even that isn't important to know because ATC will tell you to reset your code and you will reset the code. Who cares "why".
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Yeah who cares why about anything aviation? Rote memory is all that's needed. :eek:
 
EdFred said:
Yeah who cares why about anything aviation? Rote memory is all that's needed. :eek:
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Even rote memory is not needed for this. All you need to remember is that they give you a code and you enter it. Absolutely nothing bad can come from not understanding what the code means or how it is calculated. Of course, it is good for bragging rights if you can recite the bit pattern for the digits, for those that like to brag about how much they know.

edt: I will acknowledge that you need to know about the emergency codes, but for all the rest, you just enter what they tell you.
 
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I guess I just like information behind it as opposed to being a knob turning magenta line following chimp. I like to know why do I sometimes get a code that starts with a 4 and sometimes a 6 and sometimes a 0?

(which over the years I've found out)
 
JOhnH said:
That is all good information, and I agree it needs to be understood. My point is who cares whether the code they give you starts with a 0 or 1 or not, or if it doesn't start with an 8 or 9. There is no benefit to understanding that.
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You just said it’s all good information that needs to be understood. All it takes for a student pilot is 5 minutes to read that link to understand transponder codes / types of modes and realize that there are no 8s and 9s.

Now, the NBCAP? The majority of that is a waste of time to read. Even when I did ATC I think I looked through it once. You assign the code that pops up in the computer. Not hard.
 
Velocity173 said:
Now, the NBCAP? The majority of that is a waste of time to read. Even when I did ATC I think I looked through it once. You assign the code that pops up in the computer. Not hard.
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Never said you had to read it. Just stating that it is not the case that codes beginning with 0 or 1 are likely nor not to be local codes that are going to be reassigned.
 
EdFred said:
Yeah who cares why about anything aviation? Rote memory is all that's needed. :eek:
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I was probably the first to say it’s great for drunken campfire pilot trivia, and I still have the challenge out there to anyone who can describe why the pilot needs to know anything about the octal numbering scheme, or how it will harm them if they don’t know anything about it.

I, of course, know it, and teach it, but can’t find a Safety of Flight or even any minor operational reason that any pilot actually needs to know it. Other than as you said, for “pilot knowledge”.
 
JOhnH said:
Why would it matter whether anyone understands octal or not? ATC gives you a code; you enter said code. What is the problem with the fact that they don;t issue you a code that starts with 8 or 9.

It is more important to know that if you receive a code that starts with "0" or "1" that you will probably have to reset it if you are on a x-country. But even that isn't important to know because ATC will tell you to reset your code and you will reset the code. Who cares "why".
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I agree. There are many things in aviation that knowing the science or math or the how & why behind it is important and there are many things where it is unnecessary. This is in the category of the latter.
 
Means when told to squawk altitude, you're going to have problems above 7500'
 
denverpilot said:
I was probably the first to say it’s great for drunken campfire pilot trivia, and I still have the challenge out there to anyone who can describe why the pilot needs to know anything about the octal numbering scheme, or how it will harm them if they don’t know anything about it.

I, of course, know it, and teach it, but can’t find a Safety of Flight or even any minor operational reason that any pilot actually needs to know it. Other than as you said, for “pilot knowledge”.
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I can explain why knowing a little about the octal system as used in transponders would have been beneficial to me. I noticed that my Garmin *&%327 was not showing 8 or 9. I was dusting it off during some cockpit cleaning when the issue caught my attention. I contacted Garmin and they said to send the unit to them. Only a $600ish bench fee to fix it. Well, it didn't need fixing. Fortunately Google helped me learn about the 8 & 9. When I was a student pilot transponders were not part of the curriculum. Wheel landings and three-point landings were not either. We just learned to 'land'. There is a story behind the wheel landing vs three-point landing part of the modern instruction curriculum.
 
DanWilkins said:
I can explain why knowing a little about the octal system as used in transponders would have been beneficial to me. I noticed that my Garmin *&%327 was not showing 8 or 9. I was dusting it off during some cockpit cleaning when the issue caught my attention. I contacted Garmin and they said to send the unit to them. Only a $600ish bench fee to fix it. Well, it didn't need fixing. Fortunately Google helped me learn about the 8 & 9. When I was a student pilot transponders were not part of the curriculum. Wheel landings and three-point landings were not either. We just learned to 'land'. There is a story behind the wheel landing vs three-point landing part of the modern instruction curriculum.
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In a previous post I mentioned that owner/operators are well served knowing their avionics for troubleshooting.

Still don’t see anything that makes this information useful to the pilot of said owned/operated aircraft. Other than not to write up annoying squawks to the owner/operator that something is broke, that isn’t.

And said owner/operator would then know said pilot didn’t read the aircraft manuals provided by law by said owner/operator to said pilot. ;)
 
flyingron said:
Never said you had to read it. Just stating that it is not the case that codes beginning with 0 or 1 are likely nor not to be local codes that are going to be reassigned.
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I have read it and I wasn’t commenting on your post in particular. We’ve covered the NBCAP several times on other threads...which is pretty much par for the course on most topics on POA.
 
Pilawt said:
... So as not to damage the self-esteem of pilots who can't count past seven?
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Hey! You've got to keep one finger and thumb on the yoke while you're counting. That's why it's octal. ;)
 
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