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Platform for discussion: NTA and brakes

Engineers from three sectors of the industry get together with our technical department to discuss type approval and conclude that we need more harmonisation

FRANSPORT ngineers by and arge are not the most outpoken of professionals. Their vork usually keeps them fully )ccupied, some would assert nore than fully occupied, and rvhile they often have strong, hough carefully considered, vinions on transport issues here would seem to be too few )pportunities for these opinions :o be widely aired. CM is going :o provide a platform from Nhich well respected transport angineers may make known :heir views on topical issues. We ntend to hold a series of engineering forums. For the first of these, we sought the views of three engineers from three different sectors of the industry — vehicle operating, vehicle manufacturing and trailer manufacturing.

The participants were Walter Batstone, chief engineer, National Freight Consortium; Jay Cooper, technical manager (marketing), Iveco (UK); and Keith Buckby, technical consultant, York Trailer Company.

The main subject under discussion with CM'S technical editor and assistant technical editor, Bill Brock and Tim Blakemore, was goods vehicle national type approval, one of the most controversial and most topical of subjects. The scheme's phasing in period began on October 1.

Walter Batstone opened the discussion by giving his general reaction as an operating engineer to the introduction of the scheme.

"In principle", .he said, "we welcome type approval simply because eventually it should mean that whatever equipment and vehicles we buy we can operate throughout the Community (EEC) with impunity and we should not have to become involved in problems of design and performance of individual vehicles in individual EEC couniNes. But really the manufacturers are much more involved in the logistics of type approval than the operator because once an operator has registered a vehicle it operates under C and U Regulations anyway.

"Taking the consensus from all our engineers who have been consulted, in principle we do welcome the scheme as a measure of standardisation of performance of vehicles throughout the Community."

BUT we asked, do you not have any concerns about the introduction of type approval?

"Oh yes, there are a number of concerns we have. We know that national type approval, particularly as is proposed for Italy' can put a substantial 'front end' cost on. The manufacturer can't absorb that cost so it is bound to be passed on to the customer. That's my first concern.

"The second is the question of what, in the long term, will be introduced to make the operator comply with type approval requirements other than C and U Regulations. I mean this could be the thin end of the wedge.

"The third concern is that we obviously use a wide range of proprietary parts for our vehicles when we can't get the manufacturer's parts, some people call them spurious, but there are good quality proprietary parts available and unless all these manufacturers obtain component type approval then we as operators could have problems. I am thinking of exhaust silencers in particular.

"We have spoken to the DTp regarding this and we have assurances that where these parts or components meet the type approval standards then we will continue to have this flexibility to purchase them.

"That is my view as an operator. In summing up I would say that it is the long-term ramifications of type approval which concern me most, apart from the 'front end' cost."

THE QUESTION of cost must be something which concerns lveco as a vehicle manufacturer. We asked Jay Cooper: What can you tell us about the cost of type approval?

"Italy, France and Germany have had type approval for many years. When I have asked engineers from those countries what benefits have resulted from type approval for them they said 'initially very little', but as Walter quite rightly says it should eventually help to harmonise the rules governing road transport in member countries.

"That must be the ultimate aim.

"It should also help to reduce continued overleaf trade barriers eventually and establish common construction standards as regards safety, in particular safety, and the environment. Speaking as a manufacturer and especially as an EEC-based manufacturer which has had to deal with type approval for many years, the current standards set by British national type approval regulations have certainly not alarmed us too much because in mainland Europe we already have to comply with them.

"What interests us is what the future holds for type approval standards. What are the next type approval standards going to be? We've seen how the car type approval system has grown, we know the extent of the European type approval system — its quite colossal. I suppose in a few years time we could have that sort of scale.

"But coming back to the cost of it, it is very difficult really to assess this. However, this recently published article which refers to £25-30,000 for a range of vehicles is not far from the truth. Well, obviously, it depends on the size of the range but really it could easily be one and a half times that figure at a conservative guess.

"With regard to Mr Batstone's point about exhaust systems and air cleaners and, for example, how emission standards are effected, we have recently carried out some type approval inspections and one of the points of difficulty is indeed the exhaust system. This is because our vehicles, starting life as Ihd models, have exhaust tail pipes which require alteration or extensions. Such modifications can be really quite a nuisance as can moving the air cleaner to the opposite side of the vehicle.

"In summary I would say then that British national type approval holds no fears for us except in the logistics of getting it completed on time."

WE ASKED Keith Buckby: Have you had any indication about trailers being included in the type approval scheme in future?

"No," said Keith Buckby."0bviously, what the DTp wants to do is get commercial vehicle NTA well and truly out of the way before even considering the possibility of including trailers.

"But there are one or two points that have been raised so far which I find very interesting, in particular the point about general acceptance within the Community of a type-approved vehicle. I was thinking of York's particular experience in braking systems to the 71/320 directive when in 1975 York was probably one of the first trailer manufacturers to get approval.

"Now, all those approvals were in fact circulated as required to all the member countries and low and behold what happens when you try and put the first vehicle into, say, Holland? They say 'but we don't know that system' and then we had to get further approval in Holland, which seems to me to defeat the whole object of type approval.

"And for that reason quite honestly I don't want to see type approval until we get a situation where we can produce a vehicle in this country and it can go freely into any other European country and be registered and operated without having to go in for further tests.

"In other words we seek harmonisation in practice rather than just in theory, which is the case at the moment. I think we have to be honest about that."

W.B.: "Yes, the extent of NTA in some EEC countries is alarming. In Italy, for example, any change made to a type-approved vehicle including wheelbase alterations require that vehicle to be re-submitted at extra cost. I think that is a bit ridiculous and I think a single harmonised Community type approval would be much better for both operators and manufacturers. I see NTA in the UK as one step towards that goal."

J.C.: "In Germany, France and Italy they have systems very similar to ours — they have the equivalents of VTAC. Each component and vehicle has to go through the respective national type approval before it can go on to EEC type approval and it is meeting those national approvals which causes problems. In other words, there are two levels."

W.B.: "I think we could be very critical of the EEC for not pushing on with harmonised transport legislation in general. This national type approval is really putting the cart before the horse. One Community-wide type-approval scheme would be so much more sensible for manufacturers and operators."

K.B. "Another point that was raised was this question of spares. I think this is very important issue and in particular I would like to come back to braking, because the braking requirements now are such that we are seeing new types of high friction linings, new types of valve to give faster response and so on.

"I think the important thing here is that if we are not careful we could get a mixture of brake linings on a vehicle and this could give rise to dreadful instability problems.

"We are not directly involved in type approval but I can't help thinking that perhaps we are involved in something more onerous and that is self certification because as far as trailers are concerned we have to 'self-certify' unless we get say the braking system approved. So on that basis we have to guarantee that our vehicle conforms to the requirements of C and U, in other words to EEC directive 71/320.

"But once it is on the road our bit is done and then it becomes the user's responsibility. I think this needs hammering home, that it is the user's responsibility to maintain the brakes at all times to comply with the standard.

"If, for instance, a brake lining is replaced with one of a different grade, having a different coefficient friction, you could have one side of a vehicle having completely different braking characteristics from the other side. There is nothing to say that spares must be of the same standard as components fitted to the original vehicle. The legislation covers initial production, but from there on nothing."

SO ARE YOU saying, we asked, that legal responsibility lies first with the vehicle manufacturer but then passes over the spares manufacturer to the operator?

W.B.: "Absolutely. The only time an operator might find uch things wrong is at an anual test and all kinds of things an happen to a vehicle between nnual tests. For part of that ime the vehicle need not ecessarily comply with the riginal type-approval performrice requirement.

"One other thing that I am a it worried about is being flowed to continue our compoent evaluation because no/here in the legislation have I eon any mention of this, not yen in this very good document Ford Guide to National Ap'royal) that has been circulated y Ford Motor Co.

"Obviously, from time to time nanufacturers, with the coperation of operators, carry out xperiments on newly designed quipment on vehicles in the ield. Indeed, we at the National 'reight Consortium initiate ome of these tests on new. ,quipment ourselves.

"We don't necessarily wait for vehicle manufacturer to come o us to ask us to test new equipnent.

"Obviously, in most cases vhen we carry out these evaluaions we are looking for imiroved performance over that which is required by legislation, )therwise we would have little .eason for doing it. We are, for xample, looking for economy neasures and durability and reiability features, but it doesn't ilways happen that way arid it ieems to me we could be in fanger of testing equipment which could be below the sten:lards required by type approval.

"An organisation such as ours as to continually adjust our /elides and equipment to suit ;hanging customer requirenents. Furthermore, segmentaion of the business is also ;hanging constantly. Wheelbase alterations are catered for in the new type approval regulations out I am thinking more of braking systems, exhaust systems and fuel injection systems, for example, with which we are constantly experimenting in order to improve performance. It does worry me a bit that we may lose that latitude.

"Type approval would seem to be a definite disincentive to experimentation in the field. J.C.: "I think there is no doubt that type approval will tend to cast manufacturers and operators into something of a straitjacket. But having said that, it does have spin off benefits, for example in establishing a common construction standard. On the subject of wheelbase alterations I don't know if everyone is aware but the DTp has circulated a document which is asking all manufacturers to quote the longest possible wheelbase that could be used on a particular model.

"This is a move towards starting an index.

"The thinking behind such an index is that the relocation of a braking system's load-sensing valve, for example, will alter braking characteristics. It seems to me a fairly open question at the moment as to what the Dip will or won't accept.

"The way I see it is that a manufacturer is on a hiding to nothing if he doesn't go for an 11-metre overall-length vehicle. For example, if you are offering a 16-ton-gvw vehicle you would be foolish not to quote as the worst case to the DTp an 11metre overall-length vehicle and say this model can have a 28 or 29ft body with a wheelbase of x even though you don't actually make it. You have to cover yourself for the 'worst case."

W.B.: "Let's assume that a vehicle is type approved up to a maximum length wheelbase and up to 11-metre overall length and also let us assume that the maximum allowed length becomes 12 metres during the production life of this vehicle. Now what happens? Does it mean that the manufacturer can restate the maximum wheelbase under the new 12-metre maximum length?

"That is just one example. What I am really asking is what about the changes in legislation during the course of a vehicle's production life? Will changes in type approval be able to be retrospective?"

RETURNING to the question of cost we asked Keith Buckby about the effect on trailers of the new braking regulations, which come into force concurrently with the type approval scheme.

KB.: "Put simply, trailers are going to cost more money because we are going to have to fit either a load-sensing valve or anti-lock braking; in other words some form of brake modulation is now mandatory. It has to cost more."

W.B. "My contention is that in any case you cannot possibly achieve the stopping distances required under the new legislation unless you have some form of modulation."

K.B.: "In our experience very few operators are aware of these legislation changes and I think that we as manufacturers and even the technical press are guilty of not high-lighting it enough. If we think of the amendment to the C and U Regulations, it was in 1981 that it became law, to come into force October 1 this year. But people have forgotten all about it. In fact, many people haven't even seen the amendment, so often when we say to operators, 'Do you realise that your specification is no longer legal?', their reply is likely to be along the lines of 'What are you talking about?'

As far as York Trailer Company's response to the new braking regulations is concerned, I don't think we can adopt a standard. There is such a wide variation of cost between load sensing and anti-lock braking that I think it has to be an operator choice. My understanding is that the Dip favours anti-lock.

"I too think that from the operator's point of view it is a better system because it is going to need far less maintenance.

"Load sensing, be it on a vehicle or on a trailer, will need regular maintenance to ensure that the valve setting is correct. Spring settlement, for example, has an effect, so the user must make regular checks. But how frequent they should be it is difficult to say. Its going to mean checking inlet and outlet pressures and lever length and rod heights' W.B.: "In the NFC specification we require Schrader valves to be fitted at various points in the air braking system so that line pressures may be checked and, of course, such checks show up any malfunction or maladjust • continued overleaf

ment of the load-sensing valve. In our experience they are neither very reliable nor durable and we spend a lot of money on changing load-sensing valves.

"An advantage of anti-lock systems is that full-air pressure is always available at the wheels. This system is by far the better choice, it seems to me; it is much more reliable and you can tuck it up into the chassis out of harm's way. Another advantage is that it is much more sensitive.

"If we have to fit some kind of braking modulation to trailers I would go for the anti-lock system."

WE ASKED: Does Iveco offer an anti-lock system?

J.C.: "Yes, we do. It's one that we haven't fitted in the UK, but certainly in France and Italy it is used. We have our own system an adaptation of the American Rockwell one."

WE ADDED: Doesn't the use of anti-lock on trailers in a big fleet cause yet more tractor/trailer matching problems?

K.B.: "No. The DTp has said that the anti-lock system can be operated through the stop-light circuit. There are people who disagree with that. The ideal is for the system to have its own circuit. I am not absolutely convinced that the standard seven-pin plug and socket is adequate for anti-lock.

"By using the ISO supplementary plug and socket, that will allow you to have a warning light in the cab. That is the ideal and should be recommended,

but if a trailer is fitted with antilock it can be operated with non anti-lock tractive units. I think it is a good move because it is going to encourage the fitment of anti-lock as an interim measure."

WE ASKED: Would the new braking regulations actually leac to improved braking standards since the previous code ol practice called for 60 per ceni efficiency when new and 50 per cent in use, whereas the EEC requirement is for only 45 per cent?

K.B.: "Well, let's talk about the in-service figure currently 50 per cent and going down to 45 per cent. But you must bear in mind that the required trailer braking efficiency is going up by five per cent. Hitherto, a trailer was only tested for W, in other words 40 per cent at the axle, and that is going up to 45 per cent.

"Therefore the trailer will now contribute a greater share of the overall braking.

"Previously, if you were looking for an overall efficiency of 50 per cent and the trailer was only required to contribute 40, it left a lot of work for the tractive unit's brakes."

W.B.: "Clearly, an articulated vehicle's braking system should work so that it is tending to pull tractive unit and trailer apart under braking, rather than one trying to push the other. But I don't think that braking efficiencies are anything like as important as stopping distances efficiencies don't really mean very much."

J.C. "Yes, and the introduction of fade tests and responsetime tests under the new regulations are also significant, !feel."

CLEARLY THEN, CM found there was general agreement among these three engineers at least that the new braking regulations represent a step in the right direction.