PCM will and does offer a higher magrgin for succesfully transmitting and receiving a valid signal train prior to a failsafe/lockout activation as compared to PPM, period. Its a technical fact not fiction or a fish story...

PCM does not work in the presence of interference that would wreak havoc on PPM systems.

I completely disagree with this statement. The inverse is an accurate depiction of what is realized with PCM.

If the interference is bad enough to mess up PPM, the PCM system would simply go into failsafe OR hold the last setting.

Not necessarily. PCM’s ability to ignore interference that would harm PPM would offer greater resistance to interference and maintain control of the model. In the event of major interference without doubt PPM is all over the sky, while PCM is either able to interpret the modulated code and perform without harm or a failsafe/hold or combination thereof will be initialized. The resulting action of PPM is entirely unpredictable, with PCM it’s a given. Now what will work best for an individual/model individually and or cumulatively is a matter subject to interpretation.

My premise is that we want nothing in our aircraft that causes radio interference. Most of the time, if something goes bad it happens gradually. A wire start rubbing and wears through - a pushrod starts to come loose at a metal joint - all kinds of thing can cause interference. Given this scenario, PPM will glitch, giving you an indication that something is wrong and needs to be found and corrected. PCM will appear to work fine - appear is the operative word here. PCM will know that there is interference and work through the problem. Given that you do not know there is a problem and it will probably get worse, your first indication that you have a problem is when you go into failsafe or the system holds the last command - either way you have a big problem.

You make some valid points here. Most are common situations. Proper installation, routine maintenance and frequent radio ground checks will uncover most of these trouble areas. Your ascertain that PPM will forewarn you is only a maybe it may also shoot you down due to the higher likelihood of RF noise damaging the carrier/pulse position signal wave. The pulse positions can be shifted slightly by RF noise between the TX and RX. Depending on the severity of the RF noise/noise's being picked up by the RX dither or glitching may occur and be realized via eradict servo movement. PCM pulse trains do not realize this damage of the carrier wave as does PPM’s pulse position commands. PCM is looking for the existence of binary coded words; they can change in amplitude or width. This does not change the coded format. ----___----_-_-_----___-__ Is all read the same, if the code is unrecognizable a failsafe is initiated. It takes a major RF incursion for this to happen… Well beyond the time PPM went south…

This issue has been argued and discussed ad nauseum - all over the place.

I here that. Its like this you make your choices, you fly with them and you die with them, or not. There are advantges and what some see as disadvantages asscociated with the use of PCM... The same argument is true of PPM...

I have yet to loose an airplane to a PCM lockout. I did loose one many years ago with PPM due to some RF noise generated outside the aircraft. There is no gaurantee either way, unless of course you leave the model at home...