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Topic: What If The Radio Went Out During Flight?
Username: Squirrel83
Posted 2005-07-30 10:40:24 and read 5274 times.

WHAT IF THE RADIO WENT OUT AT ANY DURATION OF THE FLIGHT?

I know this is an odd question but no one has ever asked it.

I guess my first question is if it is even possible for the radio to go out during flight? If so what are the procedures? What type of backup systems do the aircrafts have to prevent this from happening, or if it does happen is there a backup radio system?

Secondly has this ever occurred before? If so when, what airline, flight ect. . .

I know these days everyone has a cell phone so could/would the pilot ever lower his altitude to make a call letting them know the radio is out - -

Topic: RE: What If The Radio Went Out During Flight?
Username: C172
Posted 2005-07-30 10:57:31 and read 5265 times.

The pilot would check his avionics equipment, mics, etc. On many aircraft there is a second radio for both convenience and redundancy. If he's sure he has an equipment failure, he'd tune the transponder to 7600, which is included somewhere in the "loss of radio communications" checklist.  checkmark 

With modern redundancy, an airliner isn't likely to completely lose its radios without losing some other very important things as well.

In GA aircraft, radio failure is much more common. Multi-colored light gun signals from the tower are used as a backup method of communication. However, the majority of pilots don't even know the signals. It helps to have it placarded in the cockpit somewhere.

On the rare day that I did lose my radios (happened on the ground), the tower's light gun was broken. We had a laugh about it afterwards in the lobby of the airport. The days of Cessna flyin'.




 dopey c172... what will he think of next? drunk 

Topic: RE: What If The Radio Went Out During Flight?
Username: HAWK21M
Posted 2005-07-30 12:14:42 and read 5227 times.

Backup systems Exist.
regds
MEL

Topic: RE: What If The Radio Went Out During Flight?
Username: N79969
Posted 2005-07-30 12:26:08 and read 5222 times.

There is also a transponder sqwak code that you dial in that alerts ATC to your problem.

Topic: RE: What If The Radio Went Out During Flight?
Username: Geoffm
Posted 2005-07-30 12:37:06 and read 5219 times.

Backups fail - extremely rarely but it is still possible.

So, taking Squirrel's question a little further, let's take a worst case scenario. If a passenger 747 lost all comms, how would it land?

Perhaps better asked in the Tech/Ops forum maybe.

Geoff M.

Topic: RE: What If The Radio Went Out During Flight?
Username: AvroArrow
Posted 2005-07-30 12:48:41 and read 5206 times.

Well if they lost ONLY the comms and not the nav equipment, IFR procedure allows them to squawk the transponder code for lost comms and continue their flightplan as filed. It then becomes the responsibility of ATC to clear the way for the aircraft.
The Canadian regulation on this is here:
http://www.tc.gc.ca/CivilAviation/Re...Affairs/cars/PART6/602.htm#602_137
I should imagine that this is the same or similar the world over?

Topic: RE: What If The Radio Went Out During Flight?
Username: Woodreau
Posted 2005-07-30 17:59:54 and read 5134 times.

It depends on when you lose it.

If you are in VMC conditions, you stay in VMC conditions and land VMC.

If you are in IMC conditions, you fly the route in the order:
- the route assigned to you, or
- if you're on a vector, to the fix you are being vectored, or
- the route that you were told to expect, or
- in the absence of any of the previous three, the route that you filed in the flight plan.

Meantime, you keep trying to talk to ATC, switch radios, switch frequencies, determine whether you have a radio problem or an audio control panel problem. squawk 7600

That's the operational procedure, you don't stop flying the airplane.

As far as the procedure for getting the radios to work, it depends on the airplane and how well you know your equipment. If you're flying a 172, and your radios stop working, try turning off the comm selector panel.

Cell phone? What number are you going to call?  Smile

Topic: RE: What If The Radio Went Out During Flight?
Username: G550
Posted 2005-07-30 18:39:43 and read 5124 times.

Quoting Woodreau (Reply 6):
Cell phone? What number are you going to call?

Call up flight service, they can talk to center or approach for you and even possibly give you center's number.

Topic: RE: What If The Radio Went Out During Flight?
Username: Jetlagged
Posted 2005-07-30 21:27:54 and read 5097 times.

THE radio? Most airliners have two if not three VHF comm radios, as well as usually a couple of HF sets. If all those fail together, the gods must be really angry, in which case you might just as well give up! If things are that bad, the ATC transponder will probably be broken too!  Smile

There's also ACARS, which would be able to send any revisions to ATC clearance in text form. I know it requres a working VHF radio, but digital data might get through where voice can't.

Topic: RE: What If The Radio Went Out During Flight?
Username: SCCutler
Posted 2005-07-30 21:49:07 and read 5088 times.

While flying in the Dallas area last spring, I did hear Regional Approach handling an AA flight (it was a "heavy") which had lost comms; they could apparently still hear the App controler, because after he instructed "AAxxxx heavy, if you can hear this transmission, squawk ident," he said "Ident received."

From that point on, for all practical purposes, it was almost like a regular arrival, with the AA plane acknowledging instructions with Idents.

For those who do not know, when I wrote "squawk ident," it relates to the "Ident" button on the transponder which, when pushed, causes the transaponder to send a special signal which is shown on the controllers radar scope. Usually used to assist controllers to quickly identify a particular aircraft in traffic (especially one squawking VFR), it is aquick and easy way to have an alternate way to respond "yep, got it."

But I can also say that, in all the years I have flown, both as a pilot and as a passenger, it was the first time I had ever heard an airliner go lost comm, and even then, it was transmit only.

As for me, I always carry a charged handheld nav/com, just in case, when I fly. A convenience in VFR conditions; a potential lifesaver in IMC.

Topic: RE: What If The Radio Went Out During Flight?
Username: 727EMflyer
Posted 2005-07-30 22:01:46 and read 5088 times.

Happened to me last weekend! I was inbound to OGG and made my call to enter charlie airspace, but didn't hear my voice over the headset, and heard no reply from the tower. Rather than enter charlie with no comms, I made a 360 where I was, tried again, failed, and switched to the second radio. This time I got through, and OGG approach didn't make any comments about my first two calls, so we assumed the primary (brand new by the way) was dead. Inbound my brother (copilot) fiddled with the dead one to no avail, but after we landed, shut down and started back up it was just fine!

Topic: RE: What If The Radio Went Out During Flight?
Username: AFHokie
Posted 2005-07-31 15:00:20 and read 4972 times.

Quoting SCCutler (Reply 9):
While flying in the Dallas area last spring, I did hear Regional Approach handling an AA flight (it was a "heavy") which had lost comms; they could apparently still hear the App controler, because after he instructed "AAxxxx heavy, if you can hear this transmission, squawk ident," he said "Ident received."

From what my brain recalls, isn't using the ident feature also a way to minimize radio trans, by having the aircraft acknowledge with an ident instead of responding with a voice trans?

Topic: RE: What If The Radio Went Out During Flight?
Username: Jush
Posted 2005-07-31 20:30:44 and read 4928 times.

Quoting N79969 (Reply 3):
There is also a transponder sqwak code that you dial in that alerts ATC to your problem.

Well dude that's the 7600 on the squawk as aforementioned.
Cheers

Topic: RE: What If The Radio Went Out During Flight?
Username: SCCutler
Posted 2005-08-01 02:39:07 and read 4880 times.

Quoting AFHokie (Reply 11):
From what my brain recalls, isn't using the ident feature also a way to minimize radio trans, by having the aircraft acknowledge with an ident instead of responding with a voice trans?

Not really; "Ident" is rarely if ever used when you are flying in the IFR system, since you are already assigned and squawking a discrete code and, therefore, readily identifiable without the necessity of an additional "squawk." Airliners are always in the IFR system under positive control.

If, on the other hand, you are flying VFR (1200), and contact a radar-equipped controller (example: one always contacts regional Approach to sequence into ADS, my home plate), he might look at he scope in the general area you reported as your position and see half a dozen potentials to be "you"; a quick "Busgsmasher one four zulu, squawk ident" can immediately isolate which plane is the right one.

While using ident might seem a novel way to reduce radio clutter, simply acknowledging an instruction takes so little time anyway, that it's not a real problem (and besides, every pilot out there would acknowledge the squawk instruction on the radio, as well, anyway!). Long-term, we will go to a system of using digital data links for receiving and acknowledging instructions (some airliners in oceanic service do this now), but for now, voice rules.

Topic: RE: What If The Radio Went Out During Flight?
Username: L-188
Posted 2005-08-01 05:04:42 and read 4864 times.

You know there was a time that airplanes didn't even have radios...it isn't a part critical for flight, unlike say the wing.

Quoting AvroArrow (Reply 5):
Well if they lost ONLY the comms and not the nav equipment, IFR procedure allows them to squawk the transponder code for lost comms and continue their flightplan as filed. It then becomes the responsibility of ATC to clear the way for the aircraft.
The Canadian regulation on this is here:
http://www.tc.gc.ca/CivilAviation/Re...Affairs/cars/PART6/602.htm#602_137
I should imagine that this is the same or similar the world over?

Pretty much the same story here north of the border in the US. Squawk inop radio if available and continue as filed.

Topic: RE: What If The Radio Went Out During Flight?
Username: Jhooper
Posted 2007-07-31 01:05:19 and read 4205 times.

Quoting Squirrel83 (Thread starter):
I know these days everyone has a cell phone so could/would the pilot ever lower his altitude to make a call letting them know the radio is out

Descending to a lower altitude to use a cell phone isn't part of any procedure. If you're in the soup, it could kill you. Always maintain the highest of the assigned, expected, or MEA altitudes. On the otherhand, a handheld radio is a great airplane-independent backup to have (and an extra set of batteries too). Climbing will improve the range on that handheld radio and keep you away from dangerous terrain. Also, if the COM radio(s) have aren't working properly, it't usually operator-error related. Check your headset connections, try the handheld mike, check the volume, check the frequency, adjust the squelch, and ensure you're transmitting on the radio you think you're transmitting on. Even if you think the radio has failed, it may just be the transmitter or reciever. Transmit in the blind because they may be able to hear you even if you can't hear them, that way you'll be able to keep them apprised of your intentions. Also, try listening up on the NAV radios because if you're able to pick up a nearby VOR, LOC, or NDB station, they may be trying to get ahold of you over those frequencies. If you're VFR, you'll want to overfly the field to determine the wind, active runway, and traffic conditions. Then enter the pattern normally and look for light gun signals from the tower. You can acknowledge by rocking your wings. If you can select a nearby nontower airport to use NORDO, that would probably be better than using Addison. Then if Addison was the only place you want to have your radio repaired, the prudent pilot would call the tower on the telephone and arrange to arrive by light-gun signals. Woodreau already explained the procedures if under IFR. You're automatically cleared for any approach at the destination airport at the ETA on the flight plan.

Quoting C172 (Reply 1):
However, the majority of pilots don't even know the signals.

They better. I've had to use them twice. Once departing Ft. Worth Alliance and once arriving College Station Easterwood. The single COM radio was one of those old types that you turn the knob and the frequency appears as mechanical digits on the face of the knob. Unfortunately, the frequency I was looking at on the knob wasn't the same frequency the radio was tuning.

Quoting Woodreau (Reply 6):
Cell phone? What number are you going to call?

Ghostbusters, of course  Smile

Quoting Jetlagged (Reply 8):
If all those fail together, the gods must be really angry, in which case you might just as well give up!

With three-bus operation on the C-5, you lose all radios and only have one INU for navigation. The plane still flies so there's no reason to "give up". I don't know if it's ever happened, but if it does it isn't your day.

Quoting AFHokie (Reply 11):
From what my brain recalls, isn't using the ident feature also a way to minimize radio trans, by having the aircraft acknowledge with an ident instead of responding with a voice trans?

You wouldn't use the IDENT feature unless you're told to by the controller. Occasionally you might hear "acknowledge with IDENT", but don't just do it on your own.

Quoting L-188 (Reply 14):
Pretty much the same story here north of the border in the US

The U.S. is south of the Canadian border  Wink

Topic: RE: What If The Radio Went Out During Flight?
Username: SlamClick
Posted 2007-07-31 01:13:31 and read 4195 times.

If all the radios go out check any DC-powered engine instrument. It should be reading zero. Check an AC-powered engine tachometer. Move the throttles and observe that the reading does not change.

These things mean that all of your engines have quit and they took the battery with them.

Glide
Land

Topic: RE: What If The Radio Went Out During Flight?
Username: CoolGuy
Posted 2007-07-31 06:29:44 and read 4119 times.

What about if a plane loses both its transponder and radios. Assume it is flying under part 121. I know it's unlikely without other systems failing too, etc. But what would the correct procedure be to land?

Topic: RE: What If The Radio Went Out During Flight?
Username: SilverComet
Posted 2007-07-31 09:45:32 and read 4081 times.

Quoting SlamClick (Reply 16):

  

In all seriousness though, it happened to one of my fellow students once, while I was still in flight school. Somehow during flight he accidentally hit the 'alternator' switch, turning it off. The instructor never noticed. After a while they ran out of juice and lost all electrics. It was a VFR flight and they were flying a CAP10, so it flew just fine without a working battery. They simply turned back to the field, did a couple of passes over the runway rocking their wings to signal lost comms and landed without further incident.

I do not know whether the instructor tried tuning the alternator back on in flight, or if he ever realised he was running on battery for the last half hour, but what i do know is that my colleague got a thorough debriefing that day. 

[Edited 2007-07-31 09:48:54]

Topic: RE: What If The Radio Went Out During Flight?
Username: Boeingfixer
Posted 2007-07-31 13:22:36 and read 4035 times.

Quoting Jhooper (Reply 15):
Quoting L-188 (Reply 14):
Pretty much the same story here north of the border in the US



Quoting Jhooper (Reply 15):
The U.S. is south of the Canadian border

The largest State in the union happens to be north of the major part of Canada and happens to be where L-188 resides.

Cheers,

John

Topic: RE: What If The Radio Went Out During Flight?
Username: Airfoilsguy
Posted 2007-07-31 13:32:37 and read 4032 times.

Wasn't there a biz jet that collided with a glider and subsequently lost all coms. The glider ripped the nose off the jet. All persons involved miraculously survived.

Topic: RE: What If The Radio Went Out During Flight?
Username: Bond007
Posted 2007-07-31 13:52:59 and read 4025 times.

Quoting SilverComet (Reply 18):
I do not know whether the instructor tried tuning the alternator back on in flight, or if he ever realised he was running on battery for the last half hour, but what i do know is that my colleague got a thorough debriefing that day.

IMO it should have been the instructor that got the "thorough debriefing", not the student ... or it that who you meant?


jimbo

Topic: RE: What If The Radio Went Out During Flight?
Username: Spruit
Posted 2007-07-31 14:49:02 and read 4007 times.

Quoting SilverComet (Reply 18):
I do not know whether the instructor tried tuning the alternator back on in flight, or if he ever realised he was running on battery for the last half hour,

Interesting comment this one!

Quoting Bond007 (Reply 21):
IMO it should have been the instructor that got the "thorough debriefing", not the student

thoroughly agree here, it's part of my FREDA check to ensure the Ammeters charging and not in the red so I would have thought it would have been the first thing he checked when it all went quiet!

Spru!

Topic: RE: What If The Radio Went Out During Flight?
Username: Jhooper
Posted 2007-08-01 09:32:37 and read 3857 times.

Quoting Boeingfixer (Reply 19):
The largest State in the union happens to be north of the major part of Canada and happens to be where L-188 resides.

oh, yea you're absolutely right. Sorry, I forgot about you guys up there  Smile

Topic: RE: What If The Radio Went Out During Flight?
Username: SilverComet
Posted 2007-08-01 10:34:49 and read 3842 times.

Quoting Bond007 (Reply 21):



Quoting Spruit (Reply 22):

You are probably right. I don't know what a FREDA check is (I'm not an instructor) and as I said I don't know what he actually did to recover electrics but he landed without the radio thats for sure.

Topic: RE: What If The Radio Went Out During Flight?
Username: Spruit
Posted 2007-08-01 12:09:42 and read 3843 times.

Well, I'm not sure about anywhere else in the world but here in England!

F = Fuel
R = Radio
E = Engine (Which Includes the Ammeter check)
D = Direction
A = Altitude

Done at regular intervals during VFR flight for PPL pilots, helps me ensure I'm still going where I want and the important things I need to keep flying are still working!

Cheers,

Spru!

Topic: RE: What If The Radio Went Out During Flight?
Username: SailorOrion
Posted 2007-08-01 15:31:15 and read 3821 times.

Quoting CoolGuy (Reply 17):
What about if a plane loses both its transponder and radios.

Well, they might still find you with the primary radar. Thus, listen to VORs, NDBs and stuff (if you get a transmission there), and continue as assigned or filed. ATC will advise others that there's a NORDO around and keep them clear.

SailorOrion

Topic: RE: What If The Radio Went Out During Flight?
Username: Starlionblue
Posted 2007-08-01 15:58:50 and read 3819 times.

Quoting SlamClick (Reply 16):
These things mean that all of your engines have quit and they took the battery with them.

Yeah but don't forget to keep trying to call ATC so that they can narrow down the search area.  Wink


BTW I recall that mnemonic oft quoted here: Aviate, Navigate, Communicate.

Topic: RE: What If The Radio Went Out During Flight?
Username: N231YE
Posted 2007-08-01 16:34:18 and read 3808 times.

This may help (for the American members at least). Scroll down to 4-3-13 Traffic Control Light Signals.

Topic: RE: What If The Radio Went Out During Flight?
Username: CoolGuy
Posted 2007-08-01 19:38:39 and read 3771 times.

Got it. So if the transponder and radio went out (and nothing else) then the protocol is to hope that ATC sees the aircraft on radar and continue as usual. Upon landing just look out for other aircraft and land without clearance from ATC.

Topic: RE: What If The Radio Went Out During Flight?
Username: SlamClick
Posted 2007-08-01 19:42:10 and read 3771 times.

Quoting Starlionblue (Reply 27):
so that they can narrow down the search area.

That is what smoke is for.

Also the ELT has its own battery. Unless a flying saucer is sucking up all the battery power for miles around at some point we have to stop stringing failures together or just jump straight to the "what if the wings fall off" question.

BTW wings don't fall off airplanes. Airplanes fall off their wings. It is, after all, the wing that does the flying.

Topic: RE: What If The Radio Went Out During Flight?
Username: Starlionblue
Posted 2007-08-01 22:02:15 and read 3737 times.

Quoting SlamClick (Reply 30):
BTW wings don't fall off airplanes. Airplanes fall off their wings. It is, after all, the wing that does the flying.

I keep trying to tell that to people who are afraid of flying! "Don't worry, wings don't fall off. If they were to break they would meet at the top of the fuselage." This is normally rewarded by either a withering look or a rather pale complexion. Big grin


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