One Prominent documentation was that of Fairbairn addressing pistol disarming. In The Israel Defense Force, Pistol disarming was honed but limited to very few positions: front from a distance of a step away or closer, rear and side from a close position.
There was really no need to concentrate on Hollywood type portrayal of hostage scenarios where pistols are put in close range to victims faces.
In the past some security personnel trained in airplane hostage scenario gun disarming. Techniques were invented by usually Fitness coaches that had a background in one Martial Art or another including fighting Arts.
Today with Airport Security Enhancement, the Pistol Threat Scenario on the Airplanes is limited to Action Films or perhaps a possibility in a remote area flights that are still not up with the airlines industries.
I am not sure if chances are greater when flying with these companies to have a pistol put to your head or to have a flight accident.
But yet there are many real life situations where citizens or even other personnel to be in a position that no one wants to be and there is no reason why not to give someone a second chance to save his life.
Since Krav Maga deals with all aspects of unarmed combat, the respect for the system is the driving force behind the development of its pistol defenses.
Remember the name Krav Maga is a name “borrowed” from the Israel Defense Force original hand to hand fighting system which was developed over 40 years in house. Although the founder Imrich Lichtenfeld used this name officially in the civilian market, his intention was not to fully disclose the essence of this training system to the public but rather leave it with the Israel Defense Force.
Unfortunately after Immi's death, thousands of other people involved in the martial arts business became Hebrew lovers, and adopted this name which became very popular in the Martial Arts community first overseas and then in Israel itself.
These thousands of people either learned from a Krav Maga Instructor impersonator or impersonated Krav Maga Instructor Impersonator themselves. There were those that realized there are so many Krav Maga Instructor Impersonators on the market, they wanted to use the name but did not want to pay for another impersonator to learn. So they legitimized themselves on the account that fraud is prevalent. Some reinvented Krav Maga on their own with the best of their Martial Arts experience. Many of these people had lineage claims composed of ridiculous lies that they could not sustain, but some took advantage with the effort to educate the public of what is real Krav Maga and constantly attempted to update their versions, in order to not lose face any further.
It is possible that anything would work in certain scenarios. But when looking for the best approach relying on the limitations of reaction time you need to pick something that will work based on that limited reaction time of both attacker and defender and will take into account all possible speed of motion to all direction and intentions that the human body is capable of.
Training aides to mimic reality could be BB pistols but or modified quality controlled real pistols that are able to provide the same quality speed and low percentage of malfunction to test the techniques and in most cases to instill confidence with the students training with them by getting as close as possible to reality training. In my career I heard of few Martial Arts instructors that tried a technique they learned somewhere with a real pistol and got shot in the hip.
The least a civilian and military instructor that his reputation important to him as much as his business drive could do is test his techniques before teaching them and if he lives in a country where certain training aids are prohibited then he would have no choice by to rely on empirical research of others.
The fact is that someone is disrespecting his own teachers system by using the same system but changing its name, or perhaps using many systems and teaching a mish mash curriculum of all he has learned in his life without being able to see the light, but in any case disrespecting deceased Imrich Lichtenfeld the creator of Krav Maga by trying to rewrite history but still using the name Krav Maga.