As a dispatcher, it is quite a routine part of my job to be in contact with pilots while flying and when on the ground. At the airline I work for (a 737 operator), we have three methods for communication with crews. Firstly is ACARS (of which ours is VHF based) and that works when the aircraft is within VHF radio coverage and at most airports we fly to. Secondly is a phone patch via ARINC (which covers our entire North America/Central America network via VHF or HF) or if operating in Europe "Stockholm Radio" via HF. Lastly, is via cellular phone which is carried on the aircraft when the aircraft is on the ground. Voice communications when in-flight generally only take place when a conversation which is not suited to ACARS needs to take place (ie. a medical situation where we need to conference in Medlink/StatMD or if the aircraft is having technical issues requiring instructions/information from Maintenance Control).

My understanding is that SATCOM is mainly used in situations where ACARS is not available or when outside of VHF coverage when a conversation with your company is needed. It seems to be the norm to have a functioning SATCOM system on wide-body aircraft which often fly ETOPS 160+ routes due to the remote locations the aircraft could be at a given time. I've also noticed it installed on some narrowbodies like 737s (WestJet, Korean Air, Qantas specifically based on the radio panels). I have heard that ACARS on these aircraft are able to switch between VHF and SATCOM for receive/transmit capabilities.

Pilots, can you elaborate on the normal use of SATCOM during your routine operations?

I assume you mean SATCOM Voice as opposed to datalink? Probably varies between operators and areas of operation, but for normal routine communications, not very often, CPDLC handles 95%+ of the comm load.

BravoOne wrote:

I assume you mean SATCOM Voice as opposed to datalink? Probably varies between operators and areas of operation, but for normal routine communications, not very often, CPDLC handles 95%+ of the comm load.

Yes, SATCOM voice is what I meant.

In corporates, not very much for ATC, but handy to make pax arrangements, call the limo, call the office followed by call the home, get the Wall Street numbers.

GalaxyFlyer wrote:

In corporates, not very much for ATC, but handy to make pax arrangements, call the limo, call the office followed by call the home, get the Wall Street numbers.

I am assuming that the second half of what you wrote is mostly joke.

My understanding is satellite phones cost something like $5 to $8 per minute to use. Would you not just keep it handy for urgent situations? Trivial situations like calling your brokerage, would risk having to reimburse the company for misuse of the satellite phone resources, no? Or maybe your employer is very kind, LOL?!

You would be surprised at how things work for the uber rich. Had guy who would email via SATCOM the Captian on his yacht. Keep in mind that the Capts quarters were less than 50' from the owners computer. The monthly bill for this service was more the the cost of the home that the accountant lived in.

No joke, compared to the $7,000 to $10,000 per hour a phone call was trivia. I’ve planned the next leg on the phone, but Ka band Internet ended that. Still pretty expensive. They understood an occasional call home for schedule change, emergency, etc. Brokerage calls would be for the passengers, of course. I had a crew, lacking awareness of the internet costs, updated their iPad Jepp View—$2,500 per update. I made everyone aware of the costs after that one.

GF

BravoOne wrote:

You would be surprised at how things work for the uber rich. Had guy who would email via SATCOM the Captian on his yacht. Keep in mind that the Capts quarters were less than 50' from the owners computer. The monthly bill for this service was more the the cost of the home that the accountant lived in.

And that’s why audits are so painful for crews. The accountants/ auditors can’t argue the Boss’s bill, can’t argue about fuel or maintenance because they don’t usually have the technical knowledge, so they’re left with arguing receipts for soda and catering. A $200,000 trip to Hawaii or China boils down to why the F/A bought strawberries at Whole Foods when the local Publix had the berries for 50 cents less. True story, by the way.

GF

SATCOM is meant to be used sparingly, at least in the Airline environment, owing to the expense. It should be used only after all other means are exhausted, with the exception for medical cases in which the health of the patient-passenger make it the primary means. My most frequent use of the tool is to get Medical Advice from our provider, as this kind of thing is urgent and can best be handled over a telephone conversation. Also Diversions are a good use of SATCOM although about half the time an ACARS message is equally appropriate.

As to Frequency, I suppose I use it for medical advice about once a month, and have only needed to communicate about diversion issues twice in 10 years. Additionally it comes in as necessary when trying to communicate with certain ATC units whose HF radio propagation is poor, and I have used it for this purpose a handful of times over the last years.

Not a pilot, but I can add my 2 cents. My employer flies often in remote areas, and as such, SATCOM is used for voice and data streaming. Sometimes for something as minor as figuring out where the hotel shuttle pickup is....

diverted wrote:

Not a pilot, but I can add my 2 cents. My employer flies often in remote areas, and as such, SATCOM is used for voice and data streaming. Sometimes for something as minor as figuring out where the hotel shuttle pickup is....

Which system are they using, Iridium, or Inmarsat?

In the past cockpit used SATCOM a lot for operational questions / fixing issues. Directly contacting the guys with the answers often worked well. The reach, quality and reliability of SATCOM was never an issue, the price though..

In relation to operating the plane—it’s peanuts. In relation to my home phone—it’s probably high to outrageous.

GF

GalaxyFlyer wrote:

In relation to operating the plane—it’s peanuts. In relation to my home phone—it’s probably high to outrageous.

GF

Yeah. I get some really funny calls every once in a while and I think it is just bored long-haul crews wanting to see if it works.

Adispatcher wrote:

Yeah. I get some really funny calls every once in a while and I think it is just bored long-haul crews wanting to see if it works.

If you accidentally dial an Inmarsat phone (requires country code, of course) from your cell or landline, you will be slammed with very expensive charges. I do not believe the charges are symmetric--I understand that it costs more to call a satphone from cell/landline, than from a satphone to call a cell/landline.

Adispatcher wrote:

GalaxyFlyer wrote:

In relation to operating the plane—it’s peanuts. In relation to my home phone—it’s probably high to outrageous.

GF

Yeah. I get some really funny calls every once in a while and I think it is just bored long-haul crews wanting to see if it works.

"Calling for training purposes..."

Starlionblue wrote:

"Calling for training purposes..."

My thoughts exactly.

Got word that a pax left his sweater at the gate.
"Wanna try the SATCOM?"
"Sure."

Go ahead and startle me with a SATCOM call over Russian airspace.

The most common use of SATCOM might be to call Medlink if we have a sick passenger.

In an 8 year career using Satcom equipped airplanes, I have used Satcom voice about 3 or 4 times. Usually it's done to get a patch through to a maintenance controller to troubleshoot an aircraft abnormality. Normal communications with dispatch are usually just as easy to do over datalink unless something is very time-critical. My employer mostly transports cargo so I would have a reduced likelihood of using it for medlink.

I think it will be interesting to see what happens in this space with some of the new satcom ideas being worked on. Instead of your big Iridium sats way out VirginGalactic and SpaceX are working on massive constellations of tiny LEO sats with the aim of having speeds and costs comparable to cell plans.

BravoOne wrote:

diverted wrote:

Not a pilot, but I can add my 2 cents. My employer flies often in remote areas, and as such, SATCOM is used for voice and data streaming. Sometimes for something as minor as figuring out where the hotel shuttle pickup is....

Which system are they using, Iridium, or Inmarsat?

Apologies for the delayed response, only just saw this. Iridium.
Cheers

With all the new Ka satcom, pretty soon you can just send texts or use a texting app from your normal cell phone.

No idea about aviation systems, but Iridium and Inmarsat ground solutions can be cheaper than $2/minute. What really gets expensive is if you are calling a number satellite to satellite i.e Iridium to Inmarsat...that's like $10/min, for ground usage.

Myriad wrote:

With all the new Ka satcom, pretty soon you can just send texts or use a texting app from your normal cell phone.

Yes, but we're not allowed to do that from the cockpit.... It isn't tested and certified.

Myriad wrote:

With all the new Ka satcom, pretty soon you can just send texts or use a texting app from your normal cell phone.

I thought these range of bands suffered from high atmospheric attenuation, i.e. rain/snow fade, that made them not so ideal for terrestrial communications. I suppose if you're up beyond the clouds it wouldn't matter. I have to study more on this.

Starlionblue wrote:

Myriad wrote:

With all the new Ka satcom, pretty soon you can just send texts or use a texting app from your normal cell phone.

Yes, but we're not allowed to do that from the cockpit.... It isn't tested and certified.

So very true. Big difference in just talking and ATC directives.