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Product Loads – the good, the bad and the ugly

Updated: May 28, 2021


In recent years there has been a trend for the Training Device Manufacturers (TDM) to transition from device loads to providing product loads for popular aircraft types. The industry is now just starting to come to terms with the implications. This week we look at these implications.

What exactly is a product load?

A product load is a software load for a Flight Simulation Training Device (FSTD) and aircraft type that is common to more than one physical FSTD. This load will contain all the possible options available on that FSTD/Aircraft type. Typically, within the load, and transparent to the operator, the TDM will have separated their software into different parts;

  • Aircraft Specific modules (maybe OEM / TDM binaries or executables)

  • FSTD common modules (tools, utilities, environment simulation, cueing algorithms, etc)

  • Aircraft and avionics options/ customer configuration selections

The idea is that any corrections or enhancements to the core load are carried out once then flowed down to all the FSTDs to which it is applicable.

Why are the TDMs doing this?

As always in our industry the principal driving factor for the TDMs is to save money; maintaining and updating multiple devices, each with its own unique software load, is a major undertaking. Doing corrections once makes for big economies and in theory should lead to more consistent loads.

There is another reason though; for the TDMs (and operators) the process of qualifying each FSTD produced is time consuming and hence expensive. One of the holy grails in simulation has been to persuade the National Aviation Authorities (NAA) to accept FSTD type certifications rather than individual device qualifications. This would see a process similar to where an aircraft is given a type certificate and then each individual aircraft produced is given a permit to fly after the aircraft manufacturer confirms compliance with a robust quality system. However becoming an authorized design organization in the regulators eyes comes at a heavy cost in terms of process and oversight. Product loads are one step further along the road to this goal. However, it must be said that the TDMs have some way to go in proving adequate, robust, quality control and of course the NAAs will need to accept each other’s FSTD type certifications for it to become practical.

This sounds great, what could possibly go wrong?

As always, the devil is in the detail. There is no doubt that there are major advantages in this approach for operators but there are drawbacks. The first one is getting fixes for your issues, the TDMs have a cycle whereby potential changes are assessed and prioritised for inclusion in the next load release. For an operator getting their issue onto that list may not be that simple, although an issue may be very important for your training if you are the only customer requesting it you may have trouble getting it put into an updated load release.

So there is every chance that, as an operator, you may well find that you receive a new load that fixes nothing for you but includes fixes for things you didn’t have a problem with. It doesn’t stop there. Having received a load update with fifty fixes to problems you didn’t know you had, you now need to test them. You may also be obliged to re-run a number of Qualification Test Guides (QTG) cases, you may even need to re-master some QTGs; imagine the conversation with your NAA “We need to re-master this test because we have had a fix to a problem we didn’t know we had and wasn’t a training problem”!

Even for the TDM there are drawbacks, principally in testing. With multiple aircraft options and simulator options there will be multiple permutations that should be tested. Add into that the fact that the hardware will probably be different on some of the devices in the field and the task becomes extreme. Then they have a problem of there being hardware in the loop, particularly those that have QTG implications, dynamic releases for example. Realistically when you receive a new load as an operator you cannot be certain your configuration and options have been fully tested.

Lets not forget also about that much feared word...regression! This has always been a problem in our industry. You receive an updated load with a number of fixes only to find that issues previously fixed seem to have returned.

Configuration Control

Just because you are using a product load on your FSTD, this will not relieve you of the obligation to maintain configuration control of your FSTD. All the TDMs provide a build report with the new loads, you will of course need these to show to your NAA as proof that you are maintaining configuration control of your device. But some of the examples we have seen fall way short of what should reasonably be expected. With a load containing fixes to other operators' issues you need the full details of the original problem, the correction and how to test it; from the evidence we have seen this is not always the case. Some load reports simply list titles of Discrepancy Reports (DR) and a list of software modules that were changed.

Long Term Viability

Unless you have been able to negotiate an exceptional deal with the TDM, or subscribe to an expensive update service, once warranty has finished, regular product load updates will probably cease. So, if you need to make a change after that, for example your NAA mandated significant updates to their devices due to a changed training requirement, then you will need to buy the latest load from the TDM, apart from the cost this may well bring with it changes you didn’t need.

If you had also negotiated the rights to source code when you bought your FSTD and the change exceeds your engineering capability you will also be faced with updating to the TDM’s latest product load. Not only will you receive the required update and the unwanted changes, but you will also lose any changes your own engineering team has made.

For both of these scenarios, operators are faced with bigger changes than perhaps they wanted and are at the mercy of the TDM on the price.

So; good, bad or ugly?

Well a bit of all three. One thing is for sure, product loads are not going to be going away anytime soon. What is evident is that, as an industry, the full implications of going to product loads have not been fully considered yet. Will the TDMs still be supporting twenty year old FSTDs with product load updates? How long until an operator is told they need to undertake a computer/hardware update in order to incorporate a mandatory update?

The issues around product loads were a topic of discussion at the Flight Simulator Engineering and Maintenance Committee (FSEMC) meeting in Utrecht in 2019. They also facilitated an exploratory meeting into “Simulator Software Release” in January this year at which representatives from operators, the TDMs and the aircraft manufacturers agreed to further investigate.

One operator recently told Sim Ops that their strategy was to always stay one load behind, let everyone else test the loads and sort out the issues!

How can Sim Ops Help?

At Sim Ops we can help you ensure that at the point of purchase this complex issue is addressed contractually; read more about our FSTD Assessment and Appraisal. We can also assist on the strategy of testing and accepting future changes by providing useful Regulatory Assistance.

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