*** Do not use this for flying refer to your AFM and company policy OM ****

The FAA started publishing 5G related NOTAMS this morning.
These NOTAM will take effect on January 19th Midnight EST. 05:00 UTC.

Click here for the FAA 5G page

Soon we will start seeing special operational bulletins for all types of airplanes. I had the chance to see some drafts.

Click here for the FAA NOTAM site

These publications address almost every conceivable aspect of total, partial failure of RALT reding, and even the remote possibility of erroneous reading but in such a manner that both RA indication on both sides of the cockpit get the same wrong reading.
These bulletins include some worrisome stuff divided into mostly five categories:
• Warning systems GPWS PWS TCAS including false alarms and wrong alarms such as descend TCAS alert at low altitude while it should be inhibited.
• Takeoff and landing performance these are mostly attributed to the possibility of wrongful Air/Ground sensing. And a plane that feels it is in the air will not let you deploy thrust reversers for example.
• Low visibility Operations – This is mostly because Radio altimeter is a must for landing when the weather is a dense fog. This impacts the dispatchability as well as the operations.
• Manual flight guidance (wrong FD position) and tail-strike protection.
• Human factor and human reaction
Note These are just examples – refer to official publications for operations

Now let’s have a look at the mitigations being put in place by the FAA, Airports, FCC and the cellular companies:

• They bumped down the power to 60% still more than Europe but still they did.
• They are establishing “landing corridors” 5G free.
• In airports that where it is not possible, they are issuing NOTAMs with operational restrictions.
• They are working hard to find Alternative Mode Of compliance (AMOC) mostly by bumping up the RA transmitter power.

EASA held sort of saying that that the FAA is out of line and the 5G commotion is “Much ado about nothing”.

So, what about Human Factors aspects. Why am I concerned.

Well, such an event has the potential of influencing human performance in some aspects.

There are going to be a whole lot of details in these new operational bulletins and briefing these so comprehensively might sway crews from other threats.
The threats implied are real. But pilots tend to address the sexy ones and not the dangerous ones – takeoff performance is a big issue. But the chances of an engine failure on a snow-covered runway exactly at V1 and at that point the RA goes berserk? They are really low.
On the other hand, over concentrating on Takeoff performance and missing something benign well the chances are much higher.
So, let’s address the real threats of no RA
• Manual flight is easy. We can always fly to the PAPI.
• Aircraft not switching to Ground mode – Normal procedures address this possibility.
• False GPWS and WS Normal procedures address these as well.
• Descend alert from TCAS at low altitude – again the chances are slim. But Situational awareness is always required.

Let us talk about some risks that we will probably not find in the AD, SAFO, and bulletins:

• Landing without altitude or wrong callouts (50 40 30 20 10) I do not know about you guys, but I haven’t landed like that in some 25 years. Those of us who fly more than one type like a privet C172 they face an even greater problem because of the cockpit height.
o One problem is hard landings.
o On the other side of that are long landings
• Autothrotle not functioning properly – This is a good time to remember Asiana 214 and monitor your airspeed.
• Seeing ghosts in the machine – this might be the biggest variable. Are we going to start seeing normal airplane behavior as wrong airplane behavior? And taking wrong and un-called for actions?
• Flying head down at low altitude. This night be caused by a few factors and is a very bad practice. Among possible causes:
o Troubleshooting at low altitude.
o Getting Non-Normal-Checklist when calling for landing checklist and going head down. (Such as ADS-B OUT RADIO ALTEMETER etc.)
o Flight guidance anomalies and not switching to Visual flight on time or switching to Visual without calling it in the cockpit hurting crew coordination.
• Over emphasis of the technical issues leading to Threat and Error Mismanagement.

Regulators and OEMs overemphasizing the technical and regulatory aspects of the problem and downplaying human factors aspects, is having the potential of becoming a model example for the point made in a previous article – “Design flaw or pilot error”

Captain Hovav Ben David

(Hovav is the former DFO of ELAL Israeli Airlines)



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