I’m going to address some of the comments here about timeline and why it takes years to field something “as simple as” a chaff/flare dispenser based on my background with store separation work.
The Self Protection Pod (SPP) was first demonstrated on an MQ-9
4 years ago. At the very minimum, with a program that is willing to be cheap and is willing to take a lot of risk (up to and including a hull lost) during the test phase, engineering work started at least a year before the demo and very likely at least 2-3 years before that demo.
From a conceptual level I don’t think a vanilla MQ-9A doesn’t have any RWR or IR gear to detect that someone have launched a missile at it. The pilot and sensor operator’s view of the world is through the nose camera and the MTS-B sensor ball. The field of view of those things is like looking around your surroundings through a soda straw. So the Situational awareness for an MQ9 pilot and sensor operator is actually pretty poor. So for chaff and flare dispenser to be effective you also need a sensor system to be able to detect that the aircraft is under threat, reject false positives and employ the chaff/flare/decoys in an effective manner. So before any engineering analysis is done for the integration, someone probably did analysis work to figure out the sensor suites needed and whether or not something like a SPP is even worth doing; this alone probably took at least 6months to do if not more. Since the SPP is operational now, somebody somewhere did the analysis work to prove that it can be effective and useful to employ. This type of information is very likely not available on the internet and is probably classified because it becomes part of the training, practice, and procedure of how best to employ an SPP effectively.
So your operational analysis guys comes back and say that a SPP should work and is worth doing; now comes all the engineering work required to actually integrate the SPP. From an aerodynamics perspective, it is critical to know that the addition of the pod will not severely affect the flying qualities of the aircraft. The pod is basically adding a big ventral tail to the aircraft, at worst this can destabilize the aircraft in yaw and at best it reduce the amount of control power available to the rudder due to both interference effects and increasing the yaw stiffness of the aircraft. So if the addition of the pod reduces the cross wind landing allowance for the aircraft the pilot needs to know. To get the aerodynamic data you traditionally need to run a bunch of wind tunnel test to get the aero deltas. Wind tunnel test are planned out 6months+ in advance at minimum and there is at least a good month or so of post wind tunnel work to build up the aerodynamic deltas tables from the wind tunnel data. The SPP is simple enough that you can probably get away with doing only CFD to get the aero-deltas which might shorten the amount of time you need to get the aero deltas from 8-9 months down to 3 depending on HPC resources available and how much of a reduced data set you are willing to accept. Again SPP seems aerodynamically simple enough that you can get away with a small data set and only do CFD simulation.
This is just the effort the quantify the effects of the pod on the flying qualities of the MQ9. The biggest challenge is the store separation analysis you need to do for the chaff and flares coming out of this pod. The MQ-9 is a pusher, so there is a real danger that the dispenser doesn’t eject a chaff or flare far enough and have it end up striking the propeller. A lot of engineering hours is needed to predict the families of trajectories the chaff and flares will take and these trajectories is needed to be predicted at varying speed, altitudes unsteady effects such as gust. To get these trajectories, you traditionally need a lot of wind tunnel time to characterize the aerodynamics of the chaff bundles and flares and to collect aero interference data for when these things are close to the pod and aircraft. Again the work here might be done with CFD here given the relatively simple geometry of a chaff bundles or flare. Even still this will be a few months of CFD simulation alone, and you still need engineering hours to convert the raw CFD data to build the aero models and run tools to simulate the tens of thousands of trajectories to prove that a prop strike is either impossible or extremely unlikely event when deployed within the launch envelopes. You will beed the trajectory data from the store sep analysis to clear the pod for a flight test.
You were probably planning for the flight test in parallel with all the flying qualities and safe separation analysis. Even after you make it to the flight test, your first set of flights will mostly be done to validate the flying qualities changes to the aircraft so you don’t even deploy any chaff or flare. For the first test where you do deploy chaff and flare, you are probably doing it at the heart of the deployment envelope where the likelihood of a mishap is the least. This is probably the test event linked at the beginning of my post from about 4 years ago. You will probably need several flights to expand that deployment envelope out to the edges of the design intent deployment envelopes. These are functional tests to make sure that the SPP can detect threats and employ chaff and flares safely. Once this is done you will need to do operational testing where the SPP is sent to test squadrons where they actually get employed in an exercise or wargame to validate the operational analysis done at the beginning of the program and to resolve any issues that needs to be resolve at the operational level. This is at least if not more than a year of testing.
This is why even though SPP first deployed flares in late 2020 the SPP is only getting fielded now in 2025; and that a lot of engineering work on the SPP was probably done a few years ahead of even the 2020 test. The SPP looks like a pretty simple pod and the chaff and flares it dispenses are pretty simple and light weight. Overall the SPP program is probably a relatively low risk program that can rely more on simulation to generate the aerodynamic data needed to clear and integrate this pod for operations; and it still took the better part of a decade to get it operational. For anything more complex than this, it becomes harder to avoid wind tunnel time and there will be more conditions that you need to analyze to make sure that your store safely separates and that it is effective. This is why weapons development and integration is extremely expensive and time intensive to do.