• Tag Archives acars
  • UA2781 lands at Midway Atoll on April 16th 2021

    Settle in, this is going to be a long one.

    Background. Oh so briefly.

    C-Band uses a 6 foot (2 meter) satellite tracking dish on ~3.5 GHz. It picks up the aircraft to ground crew communications.
    L-Band uses a 7 turn 3D printed helix (swapped out from a flaked out patch antenna only 3 days before this went down) on ~1.5 GHz. It picks up the dispatch (ground) to aircraft communications.
    What unfolds is a testament to having a fully configured and well tuned Satcom/AERO ground station. Full credit to my mate in Australia. Andrew runs the station and keeps it tip top. (Even to the point of drilling a hole in the dish to let the water drain out when it tropical pours rain!)
    As well as needing a reliable RF data source, to see something unfold in real time and share it with aviation geeks around the world, you need a real time web-based dashboard with some sort of way to string together the conversation (aka, database).
    My tool of choice is Node-RED. A low code environment with amazing power. A blog for another time.
    Over the years I have been finding ‘interesting’ ways to filter and then be alerted to ACARS messages that are out of the routine. The result is a bit of JavaScript that has a list of carefully curated words, if any are in an ACARS message from any source, I get notified, exactly how depends on the ‘severity’ of the trigger word.

    Ok, enough backstory.

    Messages are going to be tagged as follows:
    ‘Pilot’. This is Pilot to dispatch. They come via the dish.
    ‘Dispatch’. This (in this case) is the United Airlines dispatch operator. They come via the helix.
    ‘Aircraft’. This is the aircraft avionics (software). They come in via the dish.
    Names and other personal details have been redacted. (Captin Walt, if you find this, please drop me a line – I’d love to chat).

    April 16th I was minding my business when this message set the adventure in motion.

    Pilot: A254D8: 01:22:14 17-04-21 AES:A254D8 GES:50 2 .N24974 ! 5Z 2 Flight UA2781 M98AUA2781/DM FODM MSG / PGUM PMDY 16 152212 ROBERTA WOULD U PLZ CALL MY WIFE xxxxx AND LET HER KNOW WE ARE OK…xxxx THE OTHER 2 PILOTS WILL TRY LATER TODAY THANKS.

    This got my attention of course. It is very much of out of mundane.
    Worth a little look right?

    At first glance it looks ok?
    You sometimes see funky numbers in the panel on the left, so the altitude did not set me off.
    Before I could push it from my mind….. Just a few minutes latter, I saw this:

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA P QUDPCULUA-1MSG FROM WHQDM UA2781/16 PGUM PMDY SENT: 13:50:54Z HELLO UA2781, I SEE YOU ARE ON THE GROUND. PLS CALL FODM WHEN ABLE DCAFO

    Ok, so now I am really interested.
    Lets zoom in a bit…

    Right. There is no way they intended to land there!
    Now I am really intrigued and started to put the word out to a few mates. I did not tweet it as I knew it would be complicated, but still let a few avgeeks know on Discord/Messenger/Email etc.

    Pilot: GES:50 2 .N24974 ! 5Z 7 Flight UA2781 M96AUA2781/C4 DISP MSG / PGUM PMDY 16 142733 SEND FORM VIA ACARS NO CELL OR WIFI

    Sounds like the crew is getting sorted, using the aircraft ACARS system to talk to dispatch. Pretty cool.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA M QUWHQVDUA?1MSG FROM DISP UA2781-16 PGUM PMDY YOUR CLEARANCE WAS CANCELLED WITH OAKLAND, AND WE ARE STILL TRYING TO CONTACT ANYONE ON THE ISLAND, ALTHOUGH I SUSPECT THAT SOMEONE WOKE UP WHEN A 787 LANDED. PLEASE LET ME KNOW IF/WHEN YOU GET IN CONTACT WITH ANYONE ON THE GROUND

    Not sure how long ADSBx holds the history, but this what we were looking at:
    https://globe.adsbexchange.com/?icao=a254d8&lat=26.824&lon=177.129&zoom=6.0&showTrace=2021-04-16

    Midway Atoll is an emergency diversion point for ETOPS operations, so it makes sense they went there if there was an issue.
    It looks like they just followed procedure and flew straight in.

    We later read a media report that said they flew around the island a few times before landing, but we have no ACARS or ADSC data to confirm that.
    It also does not make sense to extend an emergency like that.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA W QUNDCULUA~1MSG FROM TOMC CAPT – WE ARE STILL WORKING ON RECOVERY PLAN AND WILL SHARE WITH YOU ONCE WE HAVE THE DETAILS. COULD YOU SEND YOUR FOB AND THE CURRENT AC LOCATION. ALSO, HAVE YOU HAD ANY CONTACT FROM ANYONE ON THE FIELD YET. THANKS

    FOB is Fuel On Board. Its a common way to ask or report how much gas is in the tank. (Sent in weight, either lb or kg or something else, depending on the aircraft owner, crew and region – yay for standards right?).

    Dispatch: GES:50 2 .N24974 ! 5Z 8 Flight UA2781 M97AUA2781/C5 TOMC MSG / PGUM PMDY 16 151158 CAN U EMAIL THE CAPT THE COMPLETED FUMES FORM THNX UNITED.C OM

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA M QUDPCULUA.1MSG FROM TOMC UAL2781-16 PMDY KLAX CAPT – TOMC WORKING ON GETTING SUPPORT FOR YOU. I NEED TO SEND YOU SMOKE/ODOR FORM FOR YOU TO FILL OUT AND EMAIL BACK TO ME. CAN YOU SEND EMAIL OR CALL TOMC SO WE CAN GET THIS TAKEN CARE OF. THANKS

    Ok, so from that we know they landed due to smoke somewhere in the aircraft. Probably the cockpit since the pilot/FO had to smell it. (Remember, it was a cargo flight).

    At this point I am just so stoked that the Inmarsat 143E (Cairns Australia) ground station is working so well at this stage.
    Times like this makes me feel it was all worth it.
    The crazy thing is I sent Andrew a 3D printed 7 turn helix my son printed and I built to replace his SDR-Blog Patch antenna (which was not great), Andrew just got it installed about 3 days prior and its working great.
    We are getting both sides of the conversion live!!!!
    Very excited!
    I missed this one in the timeline while was checking out other stuff….

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! AA H /OAKODYA.AT1.N2497425B581AA4E284D8965041895A4D38B4D0549116CA0870674E9F51041870E2D0A8820A084DDC375CB97499A82BCFA52E4CE8E827CE4126A009901 FANS-1/A CPDLC Message: CPDLC Uplink Message: Header: Msg ID: 11 Timestamp: 13:24:06 Message data: [freetext] PMDY ADVISES THEY CANNOT ACCEPT A B787…IM WORKING ON IT

    CPDLC is “CPDLC is a two-way data-link system by which controllers can transmit non urgent ‘strategic messages to an aircraft as an alternative to voice communications. The message is displayed on a flight deck visual display. The CPDLC application provides air-ground data communication for the ATC service.”
    They are so important and often interesting we filter them out and display them in their own table on the website.
    In this case dispatch are telling the pilot that they knew the aircraft was in distress and Midland was the best option. Dispatch is ahead of the flight (so to speak) and are trying to raise anyone on the island to ready things for the landing.

    Aircraft: While its sitting on the ground sends out automated messages from time to time.

    GES:50 2 .N24974 ! H1 5 Flight UA2781 506IUA2781#T5BG00C00C00000003Q04504U05R02H01H01301931BO1641020630CK0000CN0UF1641590EG60E0C::::::::::::::::::::::1)))0V700N00M00000707)

    Its a bit cryptic, and many of us are working on their exact meaning. Usually its stuff like engine or aircraft health and status data.

    A few of the guys were looking at background information while I was mashing the ‘refresh’ button on the data feed.

    The runway is nice and long. A few guys were looking up the runway length needed for the aircraft and its rough cargo weight.
    No problems there.
    The birds on the other hand…..

    The aircraft is still spewing out automated messages like this one:

    AES:A254D8 GES:50 2 .N24974 ! RA Q QUNDCULUA~1LTD ADVISORY UA2781/16 PGUM PMDY SENT: 17:24:00Z *LENGTHY TARMAC DELAY* THE LTD CLOCK HAS BEEN EXCEEDED. *********************** DIVERSION LTD MUST BE MANAGED BY NOC. LTD BEGINS AT ON AND ENDS AT EGRESS OR OFF. AUTOMATED MESSAGES DO NOT ALWAYS HAVE ACCURATE TIMES *********************** PILOT ACTIONS: PROCEED TO GATE OR EGRESS POINT IMMEDIATELY. NOTIFY DISPATCH/CABIN AND PAX OF STATUS AS REQUIRED. *MANDATORY IOR*

    This is a result of:
    “47 passengers spent almost six hours — longer than it usually takes to fly across the continental U.S. — sitting onboard a plane that was parked on the tarmac of Rochester International Airport in Minnesota.”
    Airlines that defy the tarmac delay rules can be fined up to $27,500 for each passenger on board the affected flight. With commercial jets routinely carrying over 200 passengers these days, that means failure to follow the tarmac delay rules could cost an airline more than $5 million in fines for a single flight. The potential for that kind of financial hit is probably enough to get the attention of even the largest airline.

    So, the aircraft has this tarmac delay built in and messages the pilots that they need to take action and keep track of the time they are on the ground.
    Even though this is a cargo flight, the aircraft share similar software regardless of their ‘cargo’, be it boxes or people.

    Back to the story.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA S QUNDCULUA~1MSG FROM DISP UA2781-16 PGUM PMDY MDY IS IN CONTACT WITH YOU NOW?

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA J QUNDCULUA~1MSG FROM TOMC CAPT – REGARDING THE GPU – I SUSPECT THE AC HAS PLENTY OF FUEL FOR THE APU AND BASED ON NOT KNOW THE CONDITION/RELIABILITY OF THE GPU, LET’S NOT USE IT AND KEEP ON THE APU PLEASE

    APU, aircraft power unit. GPU, ground power unit. The aircraft has to be kept powered up (unless going into long term cold storage – ie, not in this case). Dispatch are saying they don’t know if Midland has the gear to keep the aircraft powered, they know the onboard power unit can do it, so use that one.

    Pilot: GES:50 2 .N24974 ! 5Z 7 Flight UA2781 M14AUA2781/C5 TOMC MSG / —- —- — 174628 ROGER. APU ONLY

    They are going to use the on board aircraft power unit as its a known entity.
    Pretty cool to see the Pilot acknoladge messages from dispatch in real time via satellite from half a planet away.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA N QUNDCULUA~1MSG FROM TOMC THANKS – COUPLE ITEMS – COULD YOU GIVE ME FUEL ON BOARD DETAIL AND WHERE IS THE AC PARKED, ARE WE GOING TO NEED A TOW BAR? THANKS

    After years of reading ACARS messages I personally love the guys in dispatch almost as much as pilots now. They work so hard for the crew (and passengers). This operator is thinking way ahead and wants to be sure they have everything the crew will need to get back in the air before they even need it. A good dispatch operator will reduce the crew work load a lot (I have also seen a fair few snarky dispatch messages FWIW).

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA T QUNDCULUA~1MSG FROM TOMC CAPT – ANOTHER QUESTION CAME UP THIS MORNING AND IT’S A LONG SHOT – BY CHANCE, IS IT POSSIBLE THERE WAS A BAG/CONTAINER OF “MINI NORI MAKI”; RICE CRACKERS IN THE FLIGHT DECK?

    What. What?
    A packet of crackers?
    This cracked a few of us up.
    https://www.snackhawaii.com/products/enjoy-mini-nori-maki-4-oz
    Its a real thing, but still… bit odd for dispatch to ask the crew?

    Pilot: GES:50 2 .N24974 ! 5Z 6 M15AUA0000/C5 TOMC MSG / —- —- — 175821 FOB…70.5 PARKED NEAR LARGEST BUILDING ON AIRPORT NO TOW BAR REQUIRED PLENTY OF ROOM TO TAXI OUT

    Displatch: AES:A254D8 GES:50 2 .N24974 ! RA W QUNDCULUA~1MSG FROM TOMC EXCELLENT! THANKS – ARE YOU ALL STILL STUCK ON BOARD OR DO YOU HAVE ACCESS TO THE RAMP YET?

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA Y QUNDCULUA~1MSG FROM TOMC IF YOU ARE ABLE AND WILLING, IT WOULD BE GOOD TO HAVE A WALK AROUND THE AC TO MAKE SURE NO BIRD STRIKES INBOUND TO MDY AND CONDITION OF THE TIRES. IF WE NEED TIRES, WILL NEED TO TAKE THAT INTO ACCOUNT FOR THE CHARTER OR RESCUE FLT TO CARRY YOUR WAY. THANKS

    Again with dispatch looking ahead and working the situation.
    Also not the first time the ‘bird’ word will come into play on this adventure.

    Pilot: GES:50 2 .N24974 ! 5Z 2 M16AUA0000/C5 TOMC MSG / —- —- — 180846 NO CRACKERS. YES WE HAVE A LOADING BRIDGE. TIRES ARE FINE

    Ooookkkk, so the pilot checked for crackers….

    Displatch: AES:A254D8 GES:50 2 .N24974 ! RA G QUNDCULUA~1MSG FROM TOMC ALL GOOD NEWS – THANKS! APPARENTLY, THERE HAS BEEN HISTORY OF THESE TYPE CRACKERS GENERATING A HOT ELECTRICAL SMELL IN CONFINED SPACES AND HAVE CAUSED DIVERTS IN THE PAST. WHO KNEW! GLAD TO HEAR YOUR ABLE TO STRETCH YOUR LEGS. IF YOU ALL ARE GOING TO BE LEAVING THE AC, WE WILL NEED TO ADDRESS SHUTTING IT DOWN IF THIS HAPPENS BEFORE WE HAVE SOMEONE ELSE TO MONITOR IT. THANKS

    Crackers that smell like smoke!!!
    Bahahahah
    That’s just amazing. Those crackers have caused diverts in the past?! The stuff you learn via ACARS. Just awsome!

    Pilot: GES:50 2 .N24974 ! 5Z 0 M17AUA0000/C5 TOMC MSG / —- —- — 182343 PREFLIGHT SHOWS NO CONCERNS TIRES ARE FINE AND BRAKE TEMPS NEVER EXCEEDED NORMAL RANGE

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA N QUDPCULUA.1MSG FROM TOMC UAL2781-16 PMDY KLAX THANKS xxxxx! DO YOU KNOW WHAT FLT OPS IS PLANNING FOR YOU YET? WWHQ093E

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA S QUDPCULUA.1MSG FROM TOMC UAL2781-16 PMDY KLAX CAPT – ARE YOU ALL STILL ON THE AC WWHQ093E

    At this point I had be following along for more than a few hours and was pretty tired.
    The nice thing is that Node-RED is putting the ACARS messages into a MySQL database on a 24 rolling buffer so I could just catch up in the morning. (A few of my other-side-of-the-planet avgeek buddies kept watch).

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! C1 G .DPCULUA 171434 AGM AN .N24974 – UA2781/17 PMDY PHNL SENT: 14:34:17Z PLEASE CONFIRM BEFORE DEPARTURE: -TOTAL SOULS ONBOARD -CARGO IN THE PITS? YES OR NO -GALLEY OPTION 1,2,3,4 OR 5 1. CREW MEALS IN FC GALLEY, ALL OTHER GALLEY CARTS INSTALLED BUT EMPTY 2. ALL GALLEY CARTS ONBOARD INCLUDING CONTENTS FOR RETURN PASSENGER FLT 3. ALL GALLEY CARTS INSTALLED BUT EMPTY 4. NO GALLEY CARTS INSTALLED 5. CREW MEALS IN FC GALLEY, NO OTHER GALLEY CARTS INSTALLED REPLY UA COMM>LOAD PLANNING OR MISC LP OPBLP

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA I QUDPCULUA-1MSG FROM OPBLP UA2781/17 PMDY PHNL SENT: 14:37:09Z HELLO FROM CHICAGO . IF U PLZ MX WILL BE . LOADING AOG AND TOOLS. THEY BROUGHT W THEM. . PLZ VERIFY IT WILL B . SAME WGHT AND IN THE . BULK PIT. . . QUESTIONS – CONTACT LOAD PLANNER OPBLP

    Right, it seems while we slept a maintenance flight arrived from Hawaii with some crew and gear.
    We did not check out Satcom ACARS for them – in hindsight I will the next time something like this happens.

    Dispatch: (We got a few of these releases, so are only posting the one here)
    AES:A254D8 GES:50 2 .N24974 ! RA Z QUHDQWDUA?1DISPATCH RELEASE UA2781/17 PMDY PHNL SENT: 15:02:08Z DISPATCH RELEASE UAL2781(2781) – 17APR21 PMDY/MDY PHNL/HNL N24974/3974 B789 ———————– RLS 1 FFD AFFIRMATION: PO EMP NAME EMP NO FFD — ———- —— — CA HE GAINES 136588 NO FO AW ADAM 250443 NO ———————— RELEASED IFR TO PHNL CHI55 DEPARTURE ALTN: N/A DESTINATION ALTN: PHJR/JRF 120 ETOPS ENROUTE ALTERNATES: EA:PMDY-PHNL MIN T/O FUEL:36685 THE CAPTAIN AND DISPATCHER NAMES ON THIS RELEASE CONSTITUTES THE REQUIRED SIGNATURES PER 121.663 AND INDICATES THE PILOT%

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA A QUDPCULUA-1EPNF INFO UA2781/17 PMDY PHNL SENT: 15:02:09Z NO DANGEROUS GOODS PLANNED

    Ok looking at that message, we see PMDY (Midlands Atoll) and PHNL (Daniel K. Inouye International Airport, aka Honolulu International Airport). So we know they are going to do a short hop between islands on this flight. Probably to get more fuel in PHNL to finish their original flight to KLAX.

    Aircraft: GES:50 2 .N24974 ! 23 9 Flight UA2781 M26AUA2781/23 CDOORS CLSD / PMDY PHNL 17 150347/TIME 1745 /LOC +28.2097,-177.3793

    Pilot: GES:50 2 .N24974 ! 5Z 6 Flight UA2781 M29AUA2781/LP LOAD MSG / PMDY PHNL 17 151303 9 SOB YES CARGO GALLET OPT 1

    SOB is soles on board.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA Z QUDPCULUA-1MSG FROM OPBLP UA2781/17 PMDY PHNL SENT: 15:17:47Z COPY 9 SOB 2 IN CKPIT. 7 IN FIRST…IS THAT . CORRECT? . . . . . . QUESTIONS – CONTACT LOAD PLANNER OPBLP

    The load planer needs to know how the weight is spread out on the aircraft.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA A QUWHQVDUA?1MSG FROM DISP UA2781-17 PMDY PHNL HI ANY ETD YET? THANKS

    Usually dispatch work with the local ATC, but there is none on Midway Atoll.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA B QUWHQVDUA?1MSG FROM DISP UA2781-17 PMDY PHNL DID THE 737 TAKEOFF YET?????

    United ground support are wondering if the flight that had the maintenance guys on board has cleared the island yet.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA D QUDPCULUA-1MSG FROM OPBLP UA2781/17 PMDY PHNL SENT: 15:20:37Z PLZ VERIFY MX HAS . LOADED AN ADDITIONAL . 750 PDS IN BULK. AOG. AND TOOLS THEY BROUGHT FROM HNL ON THE . NARROW BODY . . . QUESTIONS – CONTACT LOAD PLANNER

    Pilot: GES:50 2 .N24974 ! 5Z 4 Flight UA2781 M30AUA2781/LP LOAD MSG / PMDY PHNL 17 152312 AFFIRM ALL IN 1ST

    Pilot: GES:50 2 .N24974 ! 5Z 5 Flight UA2781 M31AUA2781/C4 DISP MSG / PMDY PHNL 17 152432 ETD 1545 737 HAS LEFT

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA H QUWHQVDUA?1MSG FROM DISP UA2781-17 PMDY PHNL THX CHIDD SWED

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA I QUWHQVDUA?1MSG FROM DISP UA2781-17 PMDY PHNL CAN U PLZ LET LP KNOW THE 750 LBS TOOLS PARTS VERIFIED ON BOARD??? THX

    Pilot: GES:50 2 .N24974 ! 5Z 8 Flight UA2781 M32AUA2781/C4 DISP MSG / PMDY PHNL 17 153309 APPARENTLY WE CANT MAKE OUR WHEEELS UP TIME. MX STILL WORKING ON THE MEL ITEMS. THEY WORKING W/ TOMC

    MEL is Minumin Equipment List. ie the stuff that really really matters to fly.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA K QUWHQVDUA?1MSG FROM DISP UA2781-17 PMDY PHNL RGR THAT AND NO CURFEW EXTENTION RIGHT?

    The crew cant fly without rest. So dispatch always keep track of pilot flight hours and remind the crew when they need to rotate.

    Pilot: GES:50 2 .N24974 ! 5Z 1 Flight UA2781 M33AUA2781/C4 DISP MSG / PMDY PHNL 17 155204 300 POUNDS OF MX GEAR NOT 750 FWIW

    Pilot: GES:50 2 .N24974 ! 5Z 4 Flight UA2781 M34AUA2781/C4 DISP MSG / PMDY PHNL 17 155726 NO EXTENSION YOU WOULDNT WANT ONE B/C THESE BIRDS START SWAR MING LIKE CRAZY BUT WANTED LP TO HAVE MX GEAR WT. LETS GO TONIGH

    Ah, the birds….

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! C1 R .DPCULUA 171558 AGM AN .N24974 – /UA2781/17 PMDY PHNL SENT: 15:58:06Z CAP GAINES PLZ BE /ADVISED WE ARE RE SETTING /YOUR REST FOR A 2030 DEARTURE /PLZ ACK-THANK YOU

    Pilot: GES:50 2 .N24974 ! 5Z 7 Flight UA2781 M35AUA2781/CM CREW DESK / PMDY PHNL 17 160021 PILOT ROGER RESET FOR 2030 THNX

    By this time, some how the media had started to pick up on the adventure and they got some facts wrong or missing.
    https://www.kitv.com/story/43689476/mechanical-issue-prompts-ua-flight-to-make-emergency-landing-at-midway-atoll

    https://www.flyertalk.com/forum/united-airlines-mileageplus/2038144-ua-2781-cargo-only-lax-gum-diverts-midway-atoll-16-april-2021-a.html

    https://liveandletsfly.com/united-787-9-midway-atoll/

    And yet, things were still unfolding, so it was only half the story.

    Aircraft: GES:50 2 .N24974 ! H1 9 Flight UA2781 E14GUA2781#EIB4; 20 504.4;;6554; 21 CLOSED;CLOSED 22 NORM;NOT ACTIVE 23 CLOSED;NOT ACTIVE 24 CLOSED;NOT ACTIVE 25 CLOSED;NOT ACTIVE 26 CLOSED 27 ;18;APR;21;00:35:30

    Typical door closed message, but the timing seemed a bit off. Perhaps the crew closed it and opened it again.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA R CT AND SECURE EA CONNECTOR TO EA HEATER BELOW FD THROUGH ACCESS HATCH. TOMC

    This one left most of us a little in the dark. The heater and fan were the original issue from what we could gather. Perhaps we missed some details that they exchanged with dispatch via cell or wifi (email).

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA B QUDPCULUA-1MSG FROM OPBLP UA2781/17 PMDY PHNL SENT: 06:24:49Z GOOD EVENING. . WHEN READY TO GO, . PLEASE LET ME KNOW . IF 750 LBS OF TOOLS . WERE LOADED INTO THE . BULK COMPARTMENT. . FINAL WEIGHTS TO . FOLLOW. THANKS. . QUESTIONS – CONTACT LOAD PLANNER

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA D QUDPCULUA.1MSG FROM TOMC UAL2781-17 PMDY PHNL WORKING ON YOUR MX RELEASE NOW.

    Pilot: GES:50 2 .N24974 ! 5Z 6 Flight UA2781 M41AUA2781/LP LOAD MSG / PMDY PHNL 17 063026 TOOL ARE IN CABIN

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA G QUDPCULUA-1MSG FROM OPBLP UA2781/17 PMDY PHNL SENT: 06:31:30Z GREAT. ALL 750 LBS . IN CABIN. . . . . . . . QUESTIONS – CONTACT LOAD PLANNER

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA H QUWHQVDUA?1MSG FROM DISP UA2781-17 PMDY PHNL CA PLEASE LET ME KNOW WHEN YOU ARE READY TO GO. I NEED TO UPDATE YOUR RELEASE THANKS CHIDD

    Dispatch: (this is just part of about a 10 part flight plan release – it gives you a feel for the rest of it.
    AES:A254D8 GES:50 2 .N24974 ! C1 B .DPCULUA 180650 AGM AN .N24974 – – MESSAGE FROM CHIDD – ** PART 02 OF 04 ** . CLEARANCE . . *OFP* (FPL-UAL2781-IN -B789/H-SADE3GHIJ1J2J4J5M1P2RWXYZ/LB1D1 -PMDY0733 -M080F370 DCT MDY DCT 27N170W/M084F390 DCT 25N165W DCT ECEDO/M083F390 DCT DANNO/M069F310 BOOKE8 -PHNL0227 PHJR -PBN/A1B1C1D1L1O1S2T1 NAV/RNP2 DAT/1FANS2PDC SUR/260B RSP180 DOF/210418 REG/N24974 EET/PHZH0136 SEL/AFJM CODE/A254D8 OPR/UAL PER/D RALT/PHNL RMK/TCAS) TKOF ALTN DIST TIME FUEL 00.00 0 ARWY POSITION MC DIST TIME MOR FL MACH GS/TAS ZBO COORDINATES %2

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! C1 R .DPCULUA 180651 AGM AN .N24974 – FINAL WEIGHTS UA2781/17 PMDY PHNL SENT: 06:51:48Z ************************ TOG 374055 TOW CHG – 1130 ZFW 324855 CG 27.4 ************************ SOB 009 PSGRS 07/000 -007- (48/204) LAP 00 CREW 02/00 KIDS 00 FD JUMPSEAT-0 FA JUMPSEAT-0 ************************ FLIGHT PLAN RELEASE -2- ************************

    Pilot: GES:50 2 .N24974 ! 5Z 6 Flight UA2781 M47AUA2781/LP LOAD MSG / PMDY PHNL 17 070156 250 ONLY WE LEFT 500 HERE. IT WAS MOSTLY COKE ZERO THAT WE LEFT

    Really nice to hear that they offloaded a good amount of weight in the form of Coke Zero (I’m guessing in a gesture of good will for the Island folk to enjoy for putting them up unannounced).

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA B QUDPCULUA-1INVALID WEIGHTS UA2781/17 PMDY PHNL SENT: 07:04:49Z INVALID WEIGHTS DUE TO A CHANGE IN FINAL LOAD CONFIGURATION. THE PREVIOUSLY SENT WEIGHTS ARE NOW INVALID. NEW WEIGHTS WILL BE SENT AS SOON AS POSSIBLE.

    Dispatch are re-working the weights as a result of the maintenance guys changing the amount of tools and the Coke Zero offload.
    Its really good to see that rules and regulations are not pushed aside even in times like this.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! C1 D .DPCULUA 180706 AGM AN .N24974 – FINAL WEIGHTS UA2781/17 PMDY PHNL SENT: 07:06:24Z ************************ TOG 373555 TOW CHG – 1630 ZFW 324355 CG 27.0 ************************ SOB 009 PSGRS 07/000 -007- (48/204) LAP 00 CREW 02/00 KIDS 00 FD JUMPSEAT-0 FA JUMPSEAT-0 ************************ FLIGHT PLAN RELEASE -2- ************************

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA J QUDPCULUA-1MSG FROM OPBLP UA2781/17 PMDY PHNL SENT: 07:07:02Z COPY. ONLY 250 LBS . TOOLS IN CABIN. . . FINAL WEIGHTS RESENT.. . HAVE A GREAT FLIGHT. . . . QUESTIONS – CONTACT LOAD PLANNER

    Reminder: (FOB) Fuel was 75.5 when they landed, and is now 56.0 Running the APU for all this time took an expected hit.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA S QUDPCULUA-1FINAL WEIGHTS UA2781/17 PMDY PHNL SENT: 07:12:02Z ************************ TOG 379555 TOW CHG – 1630 ZFW 324355 CG 27.4 ************************ SOB 009 PSGRS 07/000 -007- (48/204) LAP 00 CREW 02/00 KIDS 00 FD JUMPSEAT-0 FA JUMPSEAT-0 ************************ FLIGHT PLAN RELEASE ************************
    Dispatach:
    AES:A254D8 GES:50 2 .N24974 ! RA L QUHDQWDUA?1TAKEOFF DATA ** PART 01 OF 01 ** ************************ T/O MDY 06 7800 FT 787-9 GENX-1B74-75 TEMP 21C ALT 30.12 WIND 350/4 MAG 1KT HW 4KT XW TOCG/TRIM 27.4/3.66 ************************ DRY ************************ *FLAPS 15* ** *ANTI-ICE OFF* ASSMD WT. 380.4 ASSMD TMP. 64C ************************ REDUCED EPR -.– N1 *HW* V1 VR V2 88.0 1KT 137 141 145 ************************ TW EPR N1 ATMP V1/VR/V2 0 -.– 88 64C 37/41/45 5 -.– 89 60C 35/40/45 10 -.– 91 55C 33/39/45 ************************ MAX EP

    About this time, the aircaft sent its first position report via ADSC.

    Pilot: WE CANT TAKEOFF TILL 0800Z… CAN YOU EXTEND VOID… PLEASE THANX

    Becasue of birds. They need to take off late so they are all asleep.

    Dispatch: [freetext] APPROVED AS REQUESTED. REVISED DEPARTURE TIME OF 0800Z VOID TIME 0815 [freetext] REST OF CLEARANCE REMAINS THE SAME

    When they depart from these islands with no ATC they have to get clearance from Oakland center which issues the clearance with void times meaning they have to be off in this case by 0815, if not they must get another clearance.

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! C1 M .DPCULUA 180734 AGM AN .N24974 – UA2781 MDY ==================MAINTENANCE RELEASE DOCUMENT================ NOSE/TAIL INBD FLT-DATE-LEG RLS DATE RLS STA-
    SEQ-TIME 0974/N24974 2781-16APR21-1 18APR21 MDY 01-0636Z —————————CURRENCIES————————- AUTOLAND:AUTOLAND LIMIT LAND 2 6067771 —————–INBOUND PILOT DEFECT REPORTS—————– 6166173 P 17APR21 MDY DEFECT: DEFERRING BOTH CAPT & F/O SHOULDER HEATERS PER MEL 2145U AS PRECAUTIONARY AS THEY RUN IN FLIGHT WHEN RECIRC FANS RUN REF LP 615836. ACTION: 17APR DE

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! C1 A .DPCULUA 180734 AGM AN .N24974 – UA2781 MDY ==============MAINTENANCE RELEASE DOCUMENT – CONT============= NOSE/TAIL INBD FLT-DATE-LEG RLS DATE RLS STA-SEQ-TIME 0974/N24974 2781-16APR21-1 18APR21 MDY 01-0636Z A. THE FOLLOWING MUST OPERATE NORMALLY: 1. BOTH AIR CONDITIONING PACKS. 2. AT LEAST ONE LEFT CABIN AIR COMPRESSOR. 3. AT LEAST ONE RIGHT CABIN AIR COMPRESSOR. 4. REMAINING LOWER RECIRCULATION FAN. NOTE: OPERATE LOWER RECIRC FANS SWITCH NORMALLY TO ALLOW REMAINING FAN TO OPERATE. ******** END MEL 2125L OPS PLACA

    We got another C-band (satellite dish) ADSC position update from the aircraft.
    They are on the end of the runway.

    Aircraft: GES:50 2 .N24974 ! BA 1 Flight UA2781 L84AUA2781/OAKODYA.AT1.N24974A1A05E4C3D803B9C181B08C681B0ECE6C006A800A327320034A0054FA644C1EE707A6C4E4A0100040EE5A0C48F FANS-1/A CPDLC Message: CPDLC Downlink Message: Header: Msg ID: 3 Timestamp: 08:05:57 Message data: POSITION REPORT [positionreport] Latitude: 28 09.6′ north Longitude: 176 56.1′ west Time at current position: 08:06 Flight level: 148 Next fix: Latitude: 27 00.0′ north Longitude: 170 00.0′ west ETA at next fix: 08:50 Next+1 fix: Latitude: 25 00.0′ north Longitude: 165 00.0′ west%

    Pretty typical ACARS position report from the aircraft.

    And sure enough, they are on their way to Hawaii.

    Dispatch:
    AES:A254D8 GES:50 2 .N24974 ! RA I QUDPCULUA-1GATE ASSIGN UA2781/17 PMDY PHNL SENT: 08:29:17Z *** OUTBOUND FLIGHT IS A QUICK TURN *** GATE G1 OPEN RAMP FREQ OPS FREQ EON 1026Z GROUND PWR AVAIL -YES- PLANNED GROUND TIME IS 01:00 NEXT FLT UA2781/18 PHNL KLAX ETD 1130Z

    Aircraft:
    GES:50 2 .N24974 ! B6 8 Flight UA2781 L90AUA2781/OAKODYA.ADS.N249741413323438EEC9856E8B9F0D11C71C5555498587C8112FD45F32098580453D Waypoint_Change_Event: Lat = 26.9944 Long = -169.992 Alt = 38996 feet. Time past the hour = 49m 39s FOM = 1F Next waypoint Lat = 24.9999 Long = -165 Alt = 39000 feet. ETA = 00:33:12

    Pilot: GES:50 2 .N24974 ! 5Z 3 Flight UA2781 M79AUA2781/CM CREW DESK / PMDY PHNL 17 085634 PILOT HELLO ALL 3 PILOTS WANT TO DV8 AND FLY ON 2781 HNL-LAX WHICH IS THIS PLANE AND IT LEAVES 1 HR AFTER WE BLOCK IN…

    Pilot: GES:50 2 .N24974 ! 5Z 5 Flight UA2781 M81AUA2781/CM CREW DESK / PMDY PHNL 17 085803 PILOT COULD YOU PLZ GET US LISTED ON IT… SINCE ITS A CARGO…

    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA U 01:00 NEXT FLT UA2781/18 PHNL KLAX ETD 1130Z
    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA Y QUDPCULUA-1MSG FROM OPBCM UA2781/17 PMDY PHNL SENT: 09:43:55Z /HEY CREW, THIS IS THE LATEST INFO WE’VE RECEIVED IN REGARDS TO DEVIATING ON THE CONTINUATION OF YOUR FLIGHT. THEY WILL CLEAR CUSTOMS IN HNL AND WILL NOT BE ALLOWED BACK INTO SECURE AREA BC TSA WILL BE CLOSED. UNLESS THEY CAN CONVINCE CPB TO ALLOW THEM TO STAY ON THE AIRCRAFT THEY WILL NEED TO LAYOVER. THERE IS ALSO NO ONE IN HNL AT THIS HOUR TO PREP ADDITIONAL MEALS. OPBCM DM
    Dispatch: AES:A254D8 GES:50 2 .N24974 ! RA B QUDPCULUA-1MSG FROM OPBCM UA2781/17 PMDY PHNL SENT: 09:45:59Z /FOR THE MOMENT I WILL NOT REFLECT YOU TWO DEVIATING IN YOUR PAIRINGS. IF YOU ARE ABLE TO STAY ON THE PLANE WHEN YOU GET TO HNL THEN CALL US TO UPDATE PAIRINGS/CXL HOTEL. UNTIL THEN I WILL KEEP YOUR HOTEL AND TRANSPORTATION ACTIVE. OPBCM DM

    Pilot: GES:50 2 .N24974 ! 5Z 1 Flight UA2781 M94BUA2781 SO MUCH KEEP US POSTED

    ADSC position report from the aircraft, up to the satellite, down to Andrews greound station, uploaded to ADSB Exchange.

    And with that they are safely back on track.

    I want to thank once again, the guys at ADSB Exhange for ingesting our data and putting up with me on their Discourd server, Andrew for running the 143E station and putting up with my crummy coding ‘skils’ and John in Arizona for prodding me to start this whole thing.



  • Remote control of SDRuno with MQTT and Node-RED

    This page is out of date.
    Please go to my GitHub site: https://thebaldgeek.github.io/

    Getting back to looking at HF ACARS messages again and so with that comes the need to tune to the best HF frequency. (Best is still based on propagation and is a topic for another blog).
    My HF station is in Arizona, and San Francisco is the best ground station for it to hear. New York is a close second.
    SF mostly runs on two frequencies, 6559KHz and 13276KHz with 5508KHz thrown in from time to time. NY is sort of the same but different.
    So, the question (or goal) is to be able to switch between those frequencies on some sort of time schedule. (Sort of based on day and night – ie, follow the HF propagation).

    For the longest time I got fixated on getting SDRuno to do the memory channel switching for me. Spent waaaaay to long looking for plug-ins that would do the job.
    Thought about trying to set up squelch-less scanning to do the job.
    Spent some time looking to get the RSP2 working under SDR# since it seemed to have more plug-ins and options.
    Turns out this was the wrong way of looking at the problem…. All very well to get the program to do the automatic switching – which it can’t do – but what if I want some other frequency at some other time?
    Better to have web site (Node-RED dashboard) control right?
    I mean the decoded data (the ACARS message) is displayed there anyway, so putting a button there just makes sense.
    We spent hours trying to figure out how to make it work, and minutes getting it working once we turned the problem around.

    So, long intro long.
    The key is to remove control from SDRuno and put it in the hands of the website / user / Node-RED.
    Press a button on the dashboard in one location and have it change the VFO frequency in another. Here is how we do that do.

    SDRuno can use a serial protocol called CAT. The software emulates a small subset of those CAT commands for a Kenwood TS-480 transceiver.
    What we need to do is setup a serial connection to SDRuno to send those CAT commands as needed.
    Start with a virtual serial cable. I downloaded and used http://com0com.sourceforge.net/ Simple and free. Hard to beat.
    Set up something like com3 and com4 in that program.
    Go into SDRuno and set up com3 as the CAT serial port. I just accepted the default baud, it does not really matter as even 300 baud will be overkill for changing a few frequencies. It should connect straight away.
    Now, in Node-RED running on the same computer as SDRuno add a serial node that is configured to com4.
    To prove it works, put down 2 debug nodes if you like and use them to change the frequencies back and forth.
    In short, what ever CAT commands you pump into com4 via Node-RED will come out of com3 and thus into SDRuno and the VFO will change frequency.

    Now with that working, add an MQTT node configured to your broker and connect it to your serial node.
    So now, when ever a payload is published to that topic it will be sent to com4.
    On the instance of Node-RED that is running the dashboard then, you add a button that publishes its value to the broker on that topic.
    Done.
    You now have control of the SDRuno VFO A frequency from your web page.



  • Inmarsat ACARS

    Sorry guys, did not realize that I had not blogged about my Inmarsat fun and games…..

    There are a few different ways that aircraft communicate back and forth with the airline.
    This blog is about satellite.
    There is a geostationary (not moving, very handy, no tracking needed) satellite named Inmarsat (sorry, forget the exact number, there are a few of them) that carries, among other things, aircraft data.
    To pick it up you need a small dish, an antenna, SDR (software defined radio) and a computer to run some software. We are going to be looking at the ACARS data on 1.545 GHz.

    First things first. As it happens, I knew this day was coming so have been collecting satellite dishes behind the shed for a while, turns out I kinda lot track and have about 5 of them back there…. hey, its good to have options.

    Next, you need an antenna or feed horn. So I did what all good hackers do and wound one around a toilet roll.

    Next up, attache it to the dish and see if you can get some signal.
    And we did, but the mounting was a bit unsustainable and looking out the window was also not the best, but here is how it looked for the test.

    Next thing to try was jamming it in attic.
    Let me tell you about the nice words that were expressed in getting the dish through the manhole and aligned to look at the satellite.

    There is alfoil over the roof and it really killed the signal…..
    Freddy came up with the idea of putting a pole on the side fence and hiding it behind some bushes out there, so thats what did.

    Finally we had a good strong signal and a nice solid mount.
    The eagle eye among us might notice that the feed horn is not the toilet roll. And your right.
    I modified a GPS antenna and its much better as its smaller, flat and has better gain.
    So with a 30 foot long USB lead, we now have a signal in the garage where we can use the software JAERO to decode the signal and stream it to my main dashboard.

    You can see it here; http://thebaldgeek.net:2880/ui/#!/4

    Long term my plan is to get another GPS antenna and have a second decoder running to double my data rate.

    So yeah, that’s how I pick up aircraft text messages from space.
    Cool beans.



  • Noisy computers?

    We have been interested in building a one stop shop website for all things aircraft tracking and decoding for some time.
    To this end we have put up a satellite dish to get Inmarsat messages, 136mHz antennas for ACARS and VDL data and for HF we have been running an Alinco receiver.

    Everything has been working great, but I have always struggled with a really high HF noise (static) floor. It massively impacts my ability to pickup and thus decode the weak signals coming from the aircraft all around the world (the radio at this frequency – 6mHz – can hear aircraft from pretty much around the globe). I have been tinkering with the antenna and noise suppressors and all sorts of things, but it has always not been great.

    The last straw was when this guy commented about my HF reception;
    http://forums.radioreference.com/threads/adsb-acars-vdl2-data-decoding-website-for-southern-california.383104/#post-3068413
    (At the very bottom of that thread/comment.)
    1% of the traffic. Ouch.
    But he was right, I had a feeling I was not doing great. Getting around 70 messages a day from aircraft.
    I honestly suspect any one or all of the 90 or so computer devices that are running 24×7 at the house.

    Anyway, buddies to the rescue.
    I have been chatting with two guys from Phoenix a fair bit and one of them is big into both aircraft and HF and he also noticed that he was getting more traffic than I was, but he lacked the computer skills and gear to decode them.
    So yeah, we made a deal. If he picked up the signals, I would decode them.
    Thus he has dedicated one of his radios to aircraft and I wrote some code to transfer the raw data from his place to mine where I do further decoding and display it on my website.

    BOOM! I cant believe it but we went from 70 a day to 3000+ a day.
    A.M.A.Z.I.N.G!
    We are now almost drowning in lovely lovely aircraft data from around the world.
    Both he and I are thrilled.

    You can see the data here; http://thebaldgeek.net:2880/ui/#!/5
    Its been running great for the week or so and neither of us see why that won’t be the case for a good while longer.



  • ACARS

    UPDATE! I am writing up instructions and Node-RED flow code on my GitHub page: https://thebaldgeek.github.io/

    Turns out that aircraft blat out more than just their positions.
    They also send a lot of short messages that anyone can receive and to some extent decode and make some sense of.
    This has been keeping me busy for the past month or so. Been really enjoying being distracted from other things, and my love of all things aircraft gets a good dose of love.
    The fact that I also use Node-RED to decode the messages is also very helpful as I needed a project to dive deeper into it.

    I started off with the freely available acrsdeco2 program and the real power of this program is that you can run remote instances of it and have it feed into a central server.
    I sent a Raspberry Pi and two receivers to my mate in Phoenix and have his data added to what I can pick up. The net results is that we have pretty much the whole area now covered with just the two receivers. More would be good and we will look at adding a few more in due course, but for now, the two systems working as one does the job.

    From there I added Node-RED. Doing a ton of reading got a lot of the abbreviations entered into the system and then I started filtering out the boring positions reports. I split off the airborne weather reports and engine reports.
    I then added several displays that showed this filtered and partly decoded information.
    The flow is by far and away the most complex I have done.

    If you would like to watch the messages, you can, just hit up the resulting node-RED dashboard; http://thebaldgeek.net:2880/ui/#/0

    The top line is just helpful data for me to see how much data we are handling. Some quick links to other parts of the system and weather stations at each location are included.
    Next is heavily filtered messages. At times I can see more than 1 message a second and they scroll past too fast to read, so I do some heavy filtering to slow the interesting stuff down.
    Next is an aircraft call sign filter. If you want to follow a specific aircraft, this is the tool to use.
    Next is the raw message. This way you can just what we are working with.
    Below that is a way to stop/ start the raw lightly decoded messages.
    Then you have the real interesting stuff. It is the result of the filter and should be interesting enough that we email it to a few of the guys and myself.
    Below that, the reports and a table of last seen (heard) aircraft.

    All in all, fascinating stuff.