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Night VFR and Fuse/Breaker Accessibility

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jeffrey_davidson(at)earth
Guest

Posted: Thu Jul 17, 2008 8:36 am Post subject: Night VFR and Fuse/Breaker Accessibility

I have built my Zenair 601 with the fuse block on the cabin side of the firewall.  It is not accessible to the pilot in flight.  I don't plan to try to debug electrical problems in the air.  I do, however, want to be able to fly my craft at night in VFR conditions.  I have read most of the posts on this subject in the archives.  All told, the crucial question seems to be "What fuses/breakers control a circuit that is critical to night flight?"  I have gone down the list instruments and avionics in my plane and found that either I have provided a backup power supply (battery) outside of the ship's power or that I can fly without the item in question.  I understand flight can continue with inoperative navigation lights.  (Actually, what other option is there?  Stop right there?)  The transponder is the only item that doesn't have some sort of backup, and I can't find any applicable requirement for it as far as night operating limitations are concerned.  



Here is my question:  Has anyone been successful in getting their OBAM given Night VFR operating priviledges by an FAA Inspector without any fuses/breakers being accessible in flight?  This refers to 91.205.  Locally, I have gotten answers on both sides of this issue from those that should know.     



Jeff Davidson

BobsV35B(at)aol.com
Guest

Posted: Thu Jul 17, 2008 8:49 am Post subject: Night VFR and Fuse/Breaker Accessibility

Good Morning Jeff,

  

 No expert here, but this is my take!

  

 There is no requirement for any sort of an approval for you to fly night,  or for that matter, IFR.

  

 Your operating limitation should say something to the effect that the  airplane is supposed to be operated in day VFR unless it meets the appropriate  requirements of 91.205. It is up to you, the operator, to make that  determination. No other action is required.

  

 Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

628 West  86th Street

Downers Grove, IL 60516

630 985-8502 

Stearman  N3977A

Brookeridge Air Park LL22

  

  In a message dated 7/17/2008 11:37:44 A.M. Central Daylight Time,  jeffrey_davidson(at)earthlink.net writes:

  	  Quote: 	
		  Here is    my question:  Has anyone been successful in getting their OBAM given    Night VFR operating priviledges by an FAA Inspector without any fuses/breakers    being accessible in flight?  This refers to 91.205.  Locally, I have    gotten answers on both sides of this issue from those that should know.        



Jeff  Davidson

	






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frank.hinde(at)hp.com
Guest

Posted: Thu Jul 17, 2008 9:01 am Post subject: Night VFR and Fuse/Breaker Accessibility

Sure...Not only Night VFR but IFR as well...Actually all this is a bit of a misnomer because its you the builder that determines whether the airplane is equipped for Night VFR or IFR.



The DAR/FSDO is only approving for issueing a DAY VFR airworthiness certificate...I.e for phase 1..After that its up to you to equip as necessary.



Either way none of my fuses are accessible in flight



Frank

601 HDS 400 hours

Rv 7a 300



--

dennis.glaeser(at)eds.com
Guest

Posted: Thu Jul 17, 2008 11:12 am Post subject: Night VFR and Fuse/Breaker Accessibility

Interestingly, the wording of FAR 91.205 says that spare fuses must be

accessible to the pilot in flight, but never states that the fuses must

be replicable in flight!  I guess the reg writers just assumed that if

you have fuses, there would be access to them in flight   

My fuseblocks are not accessible in flight.  The DAR asked if I had

spare fuses, and I showed him a zip-lock bag of spares I keep in the

pouch on the back of the pilot seat.  That was fine with him (and he was

observed by an FAA Inspector for my inspection).



Dennis Glaeser

RV7A



------------------------------------------------------------------------

--------

I have built my Zenair 601 with the fuse block on the cabin side of the

firewall.

It is not accessible to the pilot in flight.  I don't plan to try to

debug

electrical problems in the air.  I do, however, want to be able to fly

my craft

at night in VFR conditions.  I have read most of the posts on this

subject

in the archives.  All told, the crucial question seems to be "What

fuses/breakers

control a circuit that is critical to night flight?"  I have gone down

the

list instruments and avionics in my plane and found that either I have

provided

a backup power supply (battery) outside of the ship's power or that I

can fly

without the item in question.  I understand flight can continue with

inoperative

navigation lights.  (Actually, what other option is there?  Stop right

there?)

The transponder is the only item that doesn't have some sort of backup,

and I can't find any applicable requirement for it as far as night

operating

limitations are concerned.  



Here is my question:  Has anyone been successful in getting their OBAM

given Night

VFR operating priviledges by an FAA Inspector without any fuses/breakers

being

accessible in flight?  This refers to 91.205.  Locally, I have gotten

answers

on both sides of this issue from those that should know.     



Jeff Davidson

gyoung

Joined: 09 Jan 2006
Posts: 211
Location: Republic of Texas

Posted: Thu Jul 17, 2008 11:38 am Post subject: Night VFR and Fuse/Breaker Accessibility

The standard Op Limitations wording has approval for day VFR and night or

IFR when equipped. If your concern is the FAR wording about replacement

fuses, read it carefully. It says, IF the fuses are accessible in flight,

then you need to carry spares. It does not say that the fuses MUST be

accessible in flight, only that if they are you need to carry spares.



Regards,

Greg Young

 



[quote] --

mprather(at)spro.net
Guest

Posted: Thu Jul 17, 2008 12:39 pm Post subject: Night VFR and Fuse/Breaker Accessibility

While experimentals generally don't have to comply with the normal

certification standards, I think it's useful to read what the normal

standards say.  Here's FAR 23.1357:



Sec. 23.1357 Circuit protective devices.



(a) Protective devices, such as fuses or circuit breakers, must be

installed in all electrical circuits other than--



(1) Main circuits of starter motors used during starting only; and



(2) Circuits in which no hazard is presented by their omission.



(b) A protective device for a circuit essential to flight safety may not

be used to protect any other circuit.



(c) Each resettable circuit protective device ("trip free" device in which

the tripping mechanism cannot be overridden by the operating control) must

be designed so that--



(1) A manual operation is required to restore service after tripping; and



(2) If an overload or circuit fault exists, the device will open the

circuit regardless of the position of the operating control.



(d) If the ability to reset a circuit breaker or replace a fuse is

essential to safety in flight, that circuit breaker or fuse must be so

located and identified that it can be readily reset or replaced in flight.



(e) For fuses identified as replaceable in flight--



(1) There must be one spare of each rating or 50 percent spare fuses of

each rating, whichever is greater; and



(2) The spare fuse(s) must be readily accessible to any required pilot.



Item (d) seems most interesting to me.  Only if the ability to

reset/replace the protection is required for safety of flight must the

protection be located to be easily accessible while in flight.  All other

circuit protection can be located at the convenience of the designer. 

Further, if a fault tolerant design is adopted, the failure of no single

item should put the outcome of the flight in jeopardy.  That says that no

breakers or fuses need be accessible while in flight.  A nice side benefit

of fault tolerant designs.  Lots of airplanes have been built this way..



As far as paragraph (c) item (6) (from 91.205 that you mentioned):



"(6) One spare set of fuses, or three spare fuses of each kind required,

that are accessible to the pilot in flight."



I take the important part of that to be "fuses of each kind required". 

Since no circuit protection need be accessible according to our good and

proven design, no spare fuses are "required" to be accessible by the

pilot...

Regards,



Matt-



 	  Quote: 	
		   

 <dennis.glaeser(at)eds.com>



 Interestingly, the wording of FAR 91.205 says that spare fuses must be

 accessible to the pilot in flight, but never states that the fuses must

 be replicable in flight!  I guess the reg writers just assumed that if

 you have fuses, there would be access to them in flight 

 My fuseblocks are not accessible in flight.  The DAR asked if I had

 spare fuses, and I showed him a zip-lock bag of spares I keep in the

 pouch on the back of the pilot seat.  That was fine with him (and he was

 observed by an FAA Inspector for my inspection).



 Dennis Glaeser

 RV7A



 ------------------------------------------------------------------------

 --------

 I have built my Zenair 601 with the fuse block on the cabin side of the

 firewall.

 It is not accessible to the pilot in flight.  I don't plan to try to

 debug

 electrical problems in the air.  I do, however, want to be able to fly

 my craft

 at night in VFR conditions.  I have read most of the posts on this

 subject

 in the archives.  All told, the crucial question seems to be "What

 fuses/breakers

 control a circuit that is critical to night flight?"  I have gone down

 the

 list instruments and avionics in my plane and found that either I have

 provided

 a backup power supply (battery) outside of the ship's power or that I

 can fly

 without the item in question.  I understand flight can continue with

 inoperative

 navigation lights.  (Actually, what other option is there?  Stop right

 there?)

 The transponder is the only item that doesn't have some sort of backup,

 and I can't find any applicable requirement for it as far as night

 operating

 limitations are concerned.



 Here is my question:  Has anyone been successful in getting their OBAM

 given Night

 VFR operating priviledges by an FAA Inspector without any fuses/breakers

 being

 accessible in flight?  This refers to 91.205.  Locally, I have gotten

 answers

 on both sides of this issue from those that should know.



 Jeff Davidson

BobsV35B(at)aol.com
Guest

Posted: Thu Jul 17, 2008 4:21 pm Post subject: Night VFR and Fuse/Breaker Accessibility

Good Evening Dennis,

  

 Jut as a point of interest, the later Bonanzas have a whole passel of fuses  on the forward side of the firewall, They are quite obviously not replaceable in  flight!

  

 Do Not Archive

  

 Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

628 West  86th Street

Downers Grove, IL 60516

630 985-8502 

Stearman  N3977A

Brookeridge Air Park LL22

  

  In a message dated 7/17/2008 2:14:40 P.M. Central Daylight Time,  dennis.glaeser(at)eds.com writes:

  	  Quote: 	
		  Interestingly, the wording of FAR 91.205 says that spare fuses must    be

accessible to the pilot in flight, but never states that the fuses    must

be replicable in flight!  I guess the reg writers just assumed    that if

you have fuses, there would be access to them in flight      

My fuseblocks are not accessible in flight.  The DAR asked if I    had

spare fuses, and I showed him a zip-lock bag of spares I keep in    the

pouch on the back of the pilot seat.  That was fine with him (and    he was

observed by an FAA Inspector for my inspection).



Dennis    Glaeser

	






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jeffrey_davidson(at)earth
Guest

Posted: Fri Jul 18, 2008 12:36 am Post subject: Night VFR and Fuse/Breaker Accessibility

Thank you everyone for the replies.  My fuse block will stay where it is.

If the Inspector/DAR takes a contrary opinion, I'll just have to ask him to

educate me as Bob suggests in an old post.  



Jeff Davidson

bakerocb

Joined: 15 Jan 2006
Posts: 727
Location: FAIRFAX VA

Posted: Fri Jul 18, 2008 3:11 am Post subject: Night VFR and Fuse/Breaker Accessibility

7/18/2008



Hello Jeff, You wrote: "Has anyone been successful in getting their OBAM 

given Night

VFR operating priviledges by an FAA Inspector without any fuses/breakers 

being

accessible in flight?"



A) It is true that FAR Secs 23.1357 (d) and (e) read as follows:



"(d) If the ability to reset a circuit breaker or replace a fuse is 

essential to safety in flight, that circuit breaker or fuse must be so 

located and identified that it can be readily reset or replaced in flight.



(e) For fuses identified as replaceable in flight-



(1) There must be one spare of each rating or 50 percent spare fuses of each 

rating, whichever is greater; and



(2) The spare fuse(s) must be readily accessible to any required pilot."



B) But you are not building an airplane that must comply with Part 23, you 

are building an amateur built experimental airplane that instead needs only 

to comply with certain parts of FAR Part 91 under certain circumstances.



C) The paragraph in FAR Sec 91.205 that applies to this issue reads as 

follows:



"(6) One spare set of fuses, or three spare fuses of each kind required, 

that are accessible to the pilot in flight."



Since you also wrote:



"I have built my Zenair 601 with the fuse block on the cabin side of the 

firewall. It is not accessible to the pilot in flight."



Therefore from a regulatory viewpoint there is no need to be concerned 

about:



 "What fuses/breakers control a circuit that is critical to night flight?"



Or your access to those specific fuses while in flight.



Since your airplane will be in compliance with applicable regulations the 

inspector should not have this subject as an issue unless he has a personal 

fetish in this regard.



'OC' Says: "The best investment we can make is the effort to gather and 

understand knowledge."



PS: Also note that the inspector does not: "...... give(n) Night VFR 

operating priviledges......" Instead he issues you a set of Operating 

Limitations for your specific airplane which contain this statement:



"After completion of Phase I flight testing, unless appropriately equipped 

for night and/or instrument flight in accordance with 91.205, this aircraft 

is to be operated under VFR, day only."



This places the burden upon you to have your aircraft properly equipped for 

night and/or instrument flight after completion of Phase I flight testing, 

not on the inspector at the time of initial airworthiness inspection.



--------------------------------------------------------



Time: 09:36:03 AM PST US

From: Jeff Davidson <jeffrey_davidson(at)earthlink.net>

Subject: Fw: Night VFR and Fuse/Breaker Accessibility

I have built my Zenair 601 with the fuse block on the cabin side of the 

firewall.

It is not accessible to the pilot in flight.  I don't plan to try to debug

electrical problems in the air.  I do, however, want to be able to fly my 

craft

at night in VFR conditions.  I have read most of the posts on this subject

in the archives.  All told, the crucial question seems to be "What 

fuses/breakers

control a circuit that is critical to night flight?"  I have gone down the

list instruments and avionics in my plane and found that either I have 

provided

a backup power supply (battery) outside of the ship's power or that I can 

fly

without the item in question.  I understand flight can continue with 

inoperative

navigation lights.  (Actually, what other option is there?  Stop right 

there?)

The transponder is the only item that doesn't have some sort of backup,

and I can't find any applicable requirement for it as far as night operating

limitations are concerned.



Here is my question:  Has anyone been successful in getting their OBAM given 

Night

VFR operating priviledges by an FAA Inspector without any fuses/breakers 

being

accessible in flight?  This refers to 91.205.  Locally, I have gotten 

answers

on both sides of this issue from those that should know.



Jeff Davidson

longg(at)pjm.com
Guest

Posted: Fri Jul 18, 2008 5:36 am Post subject: Night VFR and Fuse/Breaker Accessibility

Folks,

Let's be mindful of the size of text that is continually appended to the

news list. With your thoughts exploding it's easy to forget all of what

you write and send including previous comments are duplicated on the

server. We don't want to choke that bugger. 



Strip the previous person's comments from these emails (your thoughts

are not lost) before sending. If you don't care to preserve your

comments, do not archive will drop them from record. 

Do not archive

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