SOFTWARE UPDATE

Stay tech savvy…

Ian Fraser says keep your tech up to spec with software updates…

Boeing and the FAA say they have learned a valuable lesson from the 737 Max software (SW) saga, but is there a lesson there for us too? Most modern electronic devices in our aircraft are, in effect, computers and use software (a computer program) as a key part of their function.

This approach offers manufacturers an easier and cost-effective way of designing their devices (avoiding the expensive process of redesigning electronics every time there is a minor change). They then have the ability to adjust or tweak the devices later through user (you and I) installed SW updates if something is not right or they want to add features. The downside is that while changes and fixes are easy, and thus tempting, comprehensive re-testing is still very Above Typical download page as the new software package is loaded, here on Ian’s Avmap. expensive and time consuming, however minor the change.

Software is everywhere

SW applications abound in our aircraft these days not just in the form of navigation devices in a tablet or smartphone, but also in permanently installed devices such as 8.33 radios, transponders, engine management systems, flight instrument systems, autopilots, electric trim systems, integrated glass cockpits, electrical switch systems and even intercoms. Many of them can now be updated by simply downloading a software file to your computer, then to a memory stick or card, and plugging that into your aircraft device.

Others are a little more complex. The latest devices will even update themselves automatically if they can access a Wi-Fi hub such as your smartphone’s Wi-Fi hotspot.

Users test the product

While many of the basic functions of modern electronic devices are well tested by their manufacturers before initial product release to the end user, the sheer scale and complexity of comprehensively testing the millions of permutations of data within a typical avionic device could mean testing may not have been as thorough as one might like. This has led to the aviation world adopting the computer industry ethos that customers test applications through using them.

Problems do occur, are found, fixed and regular SW updates are becoming increasingly common. Indeed, it seems that some of our well-known manufacturers / suppliers deem it OK to deliver new avionics devices with out-of-date software even if they are brand new. It’s still up to us to determine if it’s got old SW and needs an update.

Updating a new bug!

I was happily flying back from the LAA AGM a couple of years ago and having departed Sywell was heading round Northampton before tracking south to Bicester, round Oxford and on to my way home. I had the route in a portable navigator, which is linked to my autopilot, but wasn’t following it exactly, due to the runway in use not being that which I’d planned for.

Oxford Airport (near my route) sounded busy, but I didn’t want to make it worse by talking to them.

Instead, I decided to use the listening squawk but needed to look that up. Normally, I’d just temporarily engage my Autopilot (AP) while I look for things like that so would set the AP to ‘intercept’, i.e., steer a course to gradually converge with the route in my navigator, a simple one button action.

However, this time it didn’t behave as I had Top The USB slot for downloading new software into Ian’s Trig radio.

Above Memory sticks and SD cards are popular ways to load software, but some systems rely on a wi-fi connection. anticipated (when you engage an autopilot, always check that it is doing what you expect). Instead, it seemed to want to turn much further than necessary. I disengaged it, got back on the right heading and sorted out my listening squawk while hand flying. I did wonder if I was just too close to a waypoint on the route and the navigator was trying to regain the previous leg (a quirk of NMEA based GPS / AP links common to many of our AP equipped aircraft).

I flew on for a while close to my planned route until there was no doubt, and tried again. It still wanted to turn away, so I switched the AP off for about 10 seconds, back on again (which resets it) and re-engaged it.

The same happened, so it didn’t look like an AP fault. Checking the navigator this time, it still seemed to be returning to an earlier waypoint even though that was well past, and was not the nearest on route by some margin. I checked that the route in the navigator was correct and not inverted, all OK.

I reset the navigator, reloaded its route and tried again. This time it intercepted the route perfectly well

and steered the aircraft correctly through the next two waypoints. What had happened? Something went wrong, which if I had not checked could have got me seriously lost or resulted in infringement of controlled airspace. But why? It had not done this before in the five or so years that the system has been in my aircraft.

Thinking it through, I recalled that when I powered up the navigator the night before to check my route, it had prompted me that there was a SW update available and it asked, ‘did I want to install it?’.

I checked the purpose of the update before I loaded it (you should always do that) and it seemed innocuous ‘just fixing bugs, no functional change’, so I said ‘yes’. But could this ‘bug fix’ have caused my other problems (as is often the case on smart phone apps which have lots of complex software)?

What went wrong? Was it the navigator SW update? Was it me? Or was it just a random fault? I may never know, nor may the circumstances that caused it occur again either. But such is the challenge with complex SW systems.

Ideally, testing of a new device should be a comprehensive review of all operational functions in all operational scenarios if a manufacturer wants to attain any type of market credibility. However, in the case of several well-known and popular products that I have tested, I have found faults that perhaps the manufacturer should have uncovered. But never mind, they thanked me for reporting it and gave me a SW upgrade to fix it.

Non ‘approval’ of upgrades

What about the SW upgrades themselves? Do (or should) the manufacturers retest the whole device after a SW fix to see if the upgrade has affected any of the other functions? Do the authorities (LAA, CAA, EAA, FAA etc.) who govern (if anybody does) the gadgets we use require comprehensive retesting prior to an ‘approved’ SW upgrade release? No, it’s an expensive process and I’m not sure they do. It’s often just up to us to test and provide feedback.

Software is something we (and the various authorities) have to learn to live with. The comprehensive testing we used to expect for older more basic aviation electronic systems is just not affordable, or even attainable, with modern avionics. We can buy equipment to fit in our Permit aircraft which, in many cases, is far more sophisticated than the certified stuff for a fraction of its price. But there is no free lunch. The reason it is affordable (and available long before certified versions) is because corners have been cut on development and testing. It may be perfectly OK and work forever, but it may not. It’s a risk we all take.

Make sure you know which of your devices have updateable software (my aircraft has six) and what the latest version should be (see the manufacturer’s support website) – a fault may well have been discovered and fixed that you do not know about.

There are no Airworthiness Directives (ADs), Service Bulletins or Service Information Leaflets on most of our electronic devices, so be careful.

Nor will the LAA tell you there is an update. Just because an LAA (or other) approval says ‘use SW release xyz or above’ does not mean it is up to date, guaranteed, supported or tested. What it normally means is that anything less than ‘SW release xyz’ is definitely not approved, but even that doesn’t mean you can’t have it in your aircraft. You just can’t use it for what it is ‘not approved’ for.

Be vigilant

It is your responsibility to decide if you need to update SW. Is your device’s SW up to date? Have the manufacturers discovered and fixed a fault? Have they added or changed a feature? If you do update, make sure you know and are happy with what has changed. Be cautious when first using updated SW and don’t depend on it until you are confident any ‘fix’ has not broken some other aspect.

Equipment handbook issues are often aligned with SW releases. Make sure that you are using the right version of your handbook and, for your own sanity, write the SW status of your devices (portable or not) in your maintenance records or aircraft log. And check their status regularly (my tailored maintenance schedule covers it for my aircraft). But despite this, have fun with your gadgets, they add to the enjoyment and, if properly used, the safety of our hobby.

What do you think? As usual I will start a forum topic in Hangar Chat on the LAA forum.■