Unsuitable cars could be barred from future Targa Tasmania events, and other tarmac rallies, as a result of recommendations from the report into this year's fatalities.
The report by the Motorsport Australia-commissioned Investigatory Tribunal was released this week and contained 23 recommendations, all of which have been accepted by the governing body and event organiser Targa Australia.
Two of those recommendations concern the ‘identified risk', as they are referred to in the report, of “Car or its set-up not ‘Fit for Purpose'”, with a number of other recommendations tangentially related to car performance/suitability.
While suspension settings were found to be a contributing cause in the Car #602 crash which took the life of driver Shane Navin, particular emphasis was placed on that aspect of the Car #902 crash which caused the death of driver Leigh Mundy and co-driver Dennis Neagle.
Mundy lost control over a crest and crashed into trees at an impact speed of 153km/h on the Cygnet stage, which had been declared dry, and which had a tarmac surface “in generally good condition”, according to the report.
He had been driving a Porsche GT3 RS which was fitted with an optional Porsche Clubsport package, but which apparently ran in an unmodified condition, and was found to have tyres with adequate tread.
However, the Tribunal concluded that, with respect to Car #902 and “probably many others”, “the configuration of the suspension is not appropriate for the type of road conditions encountered in a road rally such as Targa Tasmania.”
The report goes on to state that, “The Tribunal further concludes that this suspension set-up, combined with the use of R tyres, induced the yaw when car 902 landed after leaving the ground at the crest, was the major contributing cause of the incident.” [sic]
While Recommendation 4 is the implementation of Restricted Time Zones ahead of particularly hazardous crests, dips, and the like, due to the identified risk of “Car leaving the ground or encountering another feature which results in loss of control through suspension design”, it is Recommendations 8 and 9 which address the identified risk of “Car or its set-up not ‘Fit for Purpose'”.
Recommendation 8 reads, “That the Organisers embark on a significant pre-entry educational campaign informing potential competitors of the risks involved with the entry of some types of vehicles or types of suspension set-ups.”
Recommendation 9 reads, “That the Organisers in conjunction with Motorsport Australia, investigate the development and implementation of a system where vehicle set-ups can be independently assessed for suitability, well prior to an event and that a written report be provided with recommendations where necessary.”
The Tribunal did not recommend limiting vehicle eligibility, but did express “serious reservations” about cars such as #902 when in the hands of inexperienced drivers.
However, neither Recommendations 8 nor 9 include guidance about what should happen if a car is deemed not suitable.
Speedcafe.com put that question to Motorsport Australia CEO Eugene Arocca, who suggested that such cars would not be permitted in the event, although advice would be taken from the Tarmac Rally Working Group which is being formed to implement the recommendations.
“I would think that if experts have reviewed the car, or the scrutineers have looked at the vehicle and decided that the car is not suitable for that particular tarmac event, then the entrant or the prospective entrant would be informed that they're not able to compete,” said Arocca.
“I think it's something that obviously the working party will consider as part of that recommendation, because there's got to be some practical realities around the responsibilities of those who examine the car, and the sort of legal responsibilities that they'll be taking on by ticking off a car.
“I think regulations can be brought in that would sheet home the consequences of a car that doesn't meet the suitability.
“Now, it should be pointed out that these events are extremely popular; both the competitive and the non-competitive element are very, very popular. High-profile competitors have been involved, some experienced racers, and people who just love motorsport.
“What we need to do is to make sure that the learnings from this event around suitability of vehicles is actioned in a way that is responsible and practical; has to be practical.
“So, I'm confident that our people will come up with a solution to deal with those pre-event inspections, and make it fair and safe.”
Arocca also expressed a view that suitability should be determined in as objective a manner as possible, adding that, “these are cars, it's mechanics, and if you're able to identify a problem with the vehicle around its suitability, generally it's pretty black and white.”
The Car #902 incident
In the case of Car #902, Motorsport Australia technical manager Scott McGrath described the incident as follows:
“The car has approached the crest on this section of road at a speed of 170 to 175 km/h, after reaching a speed of 188 km/h on the preceding section of straight road.
“The car has become airborne over the crest, appears to travel to the left-hand side of the road, which induces a yaw moment to the left (rear of the car moving left) where despite the efforts of the driver the car leaves the road making impact with the trees on the right-hand side of the road.”
Multiple witnesses submitted that cars such as the Porsche GT3 RS in question, as well as other makes/models, have suspension designed for smooth tarmac roads or race tracks.
Furthermore, a “highly qualified and respected motorsport safety engineer” provided evidence which entailed an explanation of how ‘yaw' occurs, which is included in Section 7.2.5 of the report.
“In broad terms it can be summarised that the rate at which a vehicle will yaw, i.e., rotate around it's [sic] centre of gravity, is a function of an imbalance in the forces, lateral and longitudinal, generated by the tyres, and that the lateral and longitudinal force a tyre can generate (“grip”) is strongly linked to the vertical load between the tyre and the road surface,” read the engineer's submission, in part.
It should be noted that while the incident occurred on a “quite straight” section of road, the crest in question is subject to uneven elevation change across the width of the road surface.
That unevenness is consistent with the possibility that there was variation in the vertical loads between the tyres and road surface, which would explain the yaw.
The engineer furthermore submitted that a higher grip tyre/road surface combination would lead to a “yaw acceleration and rate [that] can be higher and hence more difficult to control,” while the report notes that the R-specification tyres fitted to the car were high-grip.
Jumps are, of course, not uncommon in rally events.
However, the Tribunal noted that in such events where large jumps are common, the suspension set-ups and tyres used are “vastly different” compared to those of Targa Tasmania and other tarmac events.
In addition to the conclusions regarding vehicle design/set-up, the driver was deemed to have also contributed to the incident, given others with vehicles not fit for purpose managed to negotiate the crest without incident.
It is particularly noteworthy that, “The Tribunal also heard that the crew of 902 had been posting videos which indicated that the driver had possibly been driving the car beyond his limits or beyond the car's limits bearing in mind its design, purpose and the Targa Tasmania stage environment.”