Click here to read "An introduction to the M14P for flat-engine pilots" by Fred Abramson

VEDENEYEV ENGINES

Background and history

Under the Soviet system of aircraft design and production, Design Bureaux had the responsibility for designing aircraft/engines, which they would test until acceptance and then manufacturing would typically be given to a separate manufacturing plant.

The principal product of the Vedeneyev Design Bureau has been the M14 family of engines, but these were originally designed as the AI-14 by the Ivchenko Design Bureau at Zaparozhye in the Ukraine .

The AI-14 was originally produced in the late 1950s as a 260hp engine until the Soviet authorities made the decision to pass all piston-engine development to Ivan Vedeneyev, who had set up his own Design Bureau in Voronezh .  In the meantime Ivchenko concentrated on a range of turbine engines, which they continue today.

Vedeneyev’s first engine was the AI-14RF, which produced 300hp and this in turn led to the M14P, which was introduced in its Series I form in the early 1970s.  This produced 360hp, and Series II came out in the early 1980s, still delivering 360hp, but with a variety of internal improvements.

Under the Soviet system (above) the actual manufacture of these piston engines was given to the Voronezh Mechanical Plant (VMP) a huge State controlled organisation, also in Voronezh , making a variety of aerospace products, including the Buran space-shuttle.

After the collapse of the Soviet Union the lavish funding which Vedeneyev (also known as OKBM) and VMP previously received stopped, as did the requirement for large numbers of engines.  This made little difference to VMP, for whom the production of piston aircraft engines was a relatively small part of their business, but created a significant problem for Vedeneyev, for whom the design of engines represented approximately half their business – the remainder being aerospace gearboxes.

There was continuing large scale production of engines in the early 90s with the last completed engine being manufactured by VMP in 1994.  However they still had large numbers of major components and have continued to produce small numbers of engines since then from these pre-existing components and subassemblies.

Technical Description

The M14 series of engines is recognised as being one of the finest aircraft engines of all times.  They are:

Ø      Extremely lightweight for their power.

Ø      Very tough and reliable – the Russians operate generating sets in Siberian oil fields powered by M14Ps, which are expected to run for 20,000 hours before overhaul.

Ø      Fully ‘inverted’ with the ability to run in any attitude.

Ø      Dry-sumped, which ensures good lubrication at any attitude.

Ø      Economical, despite their power - as little as 40 litres of fuel per hour at economical cruising.  

Ø      Currently the most powerful light aircraft engines available today – in versions up to 450hp.

Ø      Beautifully made incorporating such items as roller-cam-followers and roller-rocker arms.

The Romanian involvement

Under Soviet agreements, Aerostar in Romania was designated as the production plant for Yak-52 aircraft and their sister company Aeromotors was given licence to produce M14P engines for these aircraft.  It is difficult to be sure, but it would seem to us that most Yak-52s were made for the Russian Air Force/DOSAAF in Russia and that the vast majority of these aircraft were fitted with Voronezh M14P engines from VMP, which were shipped to Romania for installation.  However Yak-52s for other customers outside Russia usually have Romanian-built engines.

Enhancing the performance of the M14P engine and the development of the M14PF

The M14P family is certainly one of the World’s legendry aircraft engines, to a certain extent because of its exceptional record in world-class aerobatic competitions, but also because of its charismatic noise and high-power output for its weight.  As the only radial engine still in production, it also has a great deal of historical interest.

The Russian National Team began asking for more power and the result was the M14PF in which the power is increased  to 400hp by changing the supercharger gearbox so that the supercharger is turned at 10.5 times engine speed rather than 8.25.  This therefore uses the same supercharger and other systems, but turns the supercharger impeller at an extremely high 30,000 rpm in order to produce the higher levels of boost necessary for greater power.

The PF engine is now well-proven after some 15 years in service. In- service testing was done with the Russian National Team and the engine was principally used in competition aircraft, such as the Sukhoi, but now has much wider application in other Yaks.  The PF is now cleared up to 500 hours TBO, with the only proviso that the normal 100 hour checks are done at 50 hour intervals.

We have now sold more than 100 ‘PF’ engines to customers all over the world and we are now fitting them to all Yaks types, both to achieve higher performance for aerobatic aircraft, but over 60% of the Yak-18Ts we sell are fitted with ‘PF’ engines to enhance take-off and climb performance.

We have found PFs to be very reliable in practice, indeed on a statistical basis, somewhat more so than standard M14Ps.  In the USA where engines can be operated ‘on condition’ several PFs are well over 1,000 hours with many over 500 hours.

Production M14PF engines

Most of the M14PF engines that we have sold have been from unused, but old-stock M14P engines, which we have bought and returned to Vedeneyev, who disassemble and convert these engines; reassemble; run on test beds and then pass to us to sell.

We have had, and indeed continue to have, a worldwide exclusive arrangement with Vedeneyev/OKBM to sell their products outside the Former Soviet Union.

Financial problems of Vedeneyev/OKBM

At the end of 2004, it became clear that there were serious financial problems with the company.  Because of this production was reduced to very small amounts, and the company was placed in a form of protective bankruptcy, similar to the US ‘Chapter 11’.

However in 2006, Vedeneyev was purchased by FK System – a major Russian group with a wide variety of interests, including the control of Kamov Helicopters.  They have injected considerable amounts of fresh capital; reorganised the business and in doing so changing it from a Soviet style organisation into a much more modern and competitive business.

This can be seen in much more efficient production methods; swifter turn-round for overhauls etc etc.

The requirement for 450hp

The Russian Air Force issued a requirement for a high-performance two-seater training aircraft powered by a piston engine, to take over from the Yak-52.  Sukhoi proposed the Su-49 – a tricycle retractable and extraction-system equipped version of the Su-29.  Yakovlev proposed the Yak-54M, a similar modification to the Yak-54 aerobatic aircraft.  In both cases the requirement was for a 450hp engine given the greater weight of the aircraft.  The potential engine requirement was going to be large and clearly of interest to both Vedeneyev/OKMB and VMP.

The requirement for more power in sport aircraft

In 2002 we could see that there was a real market for an engine that changed a single seat Sukhoi from having a power-to-ratio of just under 1 to over 1, which could totally transform the aerobatics that were possible.  We discussed this with Vedeneyev, and over a two year period, with our funding, they developed the M14R, essentially an M14P gearbox and crankcase, but with a totally re-designed supercharger and accessory case section. We had initially intended to use fuel injection, but for a variety of reasons 450hp was available with a carburettor, which meant that this was not necessary.  Also it was felt that the engine would not be considered for use by the Russian Air Force if a non-Russian fuel-injection unit was used and at that stage there were no suitable Russian versions available.

The M14R in service

We have sold a number of M14R engines, although the first 3 engines suffered identical failures in the bushings of the supercharger drive shafts, which were turning at much higher speeds and under greater load.  In all cases the engine continued to run and the aircraft landed safely.  However this led to a re-design of the defective bearings, which were changed from bushings to roller bearings and after significant amounts of testing, the engine is back in production, albeit slowly. We are putting as much pressure on Vedeneyev as possible, since we have considerable demand for these engines.  The capability of the M14R engine is demonstrated by the fact that overall victor of the 2007 World Aerobatic Championships was Ramon Alonso of Spain flying his M14R equipped Sukhoi Su-31 aircraft – there can be no tougher test of an engine.

M9F engine

VMP began looking at ways of achieving the requirements for the Sukhoi Su-49 and for political reasons a bond had already been established between VMP and Sukhoi for this engine.  A major problem was that the Su-49 has hydraulic rather than pneumatic systems and therefore the engine has to have a hydraulic pump as part of its ancillaries.

Vedeneyev/OKBM had previously developed an engine called the M14B (300hp) for the Antonov A14, which had been totally re-designed to accommodate a hydraulic pump behind the supercharger.  VMP decided that this engine should be the basis of their higher power engine, which they called the M9F, indicating that it is radically different from both the M14B and indeed the M14P.

Inevitably, with two design teams working towards the same goal their results have been similar, although very different in detail.  The M9F is considerably modified from the M14P as can be seen by the photograph below in which the items unique to the M9F are coloured in yellow.

Yellow indicates the part unique to the M9F                                                 Fuel Injection system  

In 2003 Sukhoi decided to upgrade the Su-26M into the Su-26M3 and this aircraft was fitted with the M9F engine.  This combination of engine and airframe has won every world and European Championship since then, with the exception of the recent 2007 World Aerobatic Championship where the Russian Team Su-26M3s came third, fourth and seventh, as well as winning the team prize.

Like the M14R, we have an exclusive arrangement with VMP for the supply of M9F engines, and have done all we can to get regular supplies. However VMP received, in the middle of 2007, an order for 120 new M14P engines, principally for 60 new Yak-18T aircraft for the Russian Ministry of Transport.  This has meant that their energies are totally directed to this big contract and we are not sure when more M9F engines might be available.  However we have sold four of them; one powered an American-owned Su-26M which won the Freestyle gold medal at the 2007 World Championships – certainly the most demanding element of the championships.

The requirement for the Su-49 was 450hp and it is intended to achieve this with the M9F with fuel injection becoming the M9FS.  The Russian system which has been developed is electronic, injecting fuel into each separate intake under high pressure.  It also has a mechanical reversion, so if the electronic system fails, the engine will continue to run, albeit giving less power.

I have seen the fuel injection system demonstrated showing an almost instantaneous reversion to mechanical injection, with the engine giving approximately 15% less power but clearly running perfectly well.

Starting the engine is significantly simplified with no need for a primer and what is particularly impressive is the engine’s ability to go from idle to high power settings with none of the normal hesitation.

It is intended that the fuel injection will be offered as a stand-alone alternative to the carburettor, giving enhanced power but also considerably improved economy.  We are not yet sure when this will be, or of the costs.

M14R –v- M9F

Of course both Vedeneyev/OKBM and VMP say that their high-powered engines are better than the other!  Both have been very thoroughly developed and the real difference is that the M14R has a more radical impeller and infuser design, as well as turning the impeller at higher speeds.  Conversely the M9F is probably stronger in the supercharger area by virtue of larger bearings and reinforcement to take the hydraulic drive from the rear of the engine.

The other products of VMP

VMP also see a revived future introducing a range of small radial engines.  The first is the M5 (5 cylinders) but a smaller engine by virtue of a shorter stroke, albeit keeping the same cylinders as the M14P.  Current power is 170hp for a weight of 135kgs.  The next engine is the M7 (7 cylinders) which is still under development, currently giving 270hp for a weight of 170kgs.

The future

Given the many hundreds of aircraft, both of original Russian design but also new types utilizing the M14 family of engines, the future of engine and component supplies is critical.  The order for 120 new engines from VMP is clearly a major step in securing future supplies of spares, and a further positive note is that Vedeneyev have established their own foundry and large machine shop in order to produce all major components themselves, rather than be dependant on components from VMP as they have done historically.

Exchange PF supercharger assemblies

With this procedure we sell the entire rear of the engine – that is everything behind the crank case including all of the ‘PF’ conversion kit built into the supercharger and all ancillary drives.

This conversion is a straight ‘bolt-on’ conversion, although the engine needs to be removed from the aircraft and all accessories (magnetos, carburettor, oil pump etc) need to be changed.  Finally the carburettor needs to be readjusted to cope with the different mixture requirements of the PF.

We offer this conversion at Euro 4,000 on an exchange basis for the old unit.

PF gearboxes

The original M14P has output shaft with radial splines to mate with corresponding splines on the Russian V-530 propeller.  Most PF engines have been intended for use with the German MTV-3 and MTV-9 propellers and so have been delivered with American SAE flanges.  However, MT now makes propellers with both Russian and Western flanges, so effectively these are interchangeable.

We can supply exchange gearboxes incorporating either flange for Euro 2,500 on an exchange basis.

Prices

We have seen engine prices go from approximately US$8,000 up to current figures which are far higher as the large number of engines that had been available from Russian flying clubs and DOSAAF airfields have been used.  Prices are still rather less than Western engines, but our view is that these prices will continue to increase.    Currently the prices that we have to pay for engines and components have become dramatically greater over the last 18 months or so.  Our prices are subject to change without notice, but are currently:

Ø      Factory zero-time M14P (360hp) Euro 18,500

Ø      Factory new engines (ie unused but old stock) 360hp Euro 23,500 – but we have not had any to sell for over one year.

Ø      Factory zero-timed M14PF (400hp) Euro 23,500

Ø      Factory new M14PF (400hp) Euro 31,000 (when available but see below)

Ø      Factory new M14R and M9F engines Euro 44,000

You should note that the zero-time engines:

Ø      Are from Vedeneyev themselves

Ø      Incorporate all the latest Service Bulletins and modifications.

Ø      Typically have all major components,  such as cylinders replaced with new.

Ø      Are built by the most experienced engineers in the world on these engines, with access to all necessary spare parts, assembly tooling and documentation.

Ø      Are properly dynamometer tested rather than simply run up in an airframe.

Ø      Are guaranteed and supported by ourselves

These prices are FCA White Waltham, UK.  Please contact us for current availability.

Overhauls

We have initiated a programme of returning engines to Vedeneyev for total overhaul to their ‘zero-time’ standards.  The total cost of this today is Euro 14,000, which covers all costs for an engine starting at our base at White Waltham airfield UK . It covers transportation to and from Russia ; Russian customs costs; the total overhaul; painting to a high standard; proper dynamometer testing etc etc.  This price is for an engine that is still running, although clearly needing an overhaul.  For engines that have had a ground strike, or suffered hydraulic lock etc, the price is likely to be higher.

Propellers

The Russian V-530 propeller cannot transmit more than 370/380hp, and if an engine with greater power is installed, then one should go to the MTV-9-250/260 prop.  The following important points should be noted:

Ø      The standard ‘Lycoming’ 6-bolt flange is at the limits of reliability with 400hp and unlimited level aerobatics.

Ø      The Russian flange is safe in excess of 500hp since the bolts are larger and the radial splines provide better location for the hub on the flange. 

Ø      MTV-9 propellers are made with either Russian or Western flanges at the same price, as are the 250 or 260 blades.

Ø      The standard propeller blade profile is called the –27.  We were looking for propellers for the M14R, and did not want to exceed 260cm for reasons of ground clearance on a normal Sukhoi and therefore asked MT if they could provide a propeller capable of transmitting more power but with no increase in diameter.  The result has been the –29 wide chord blade, which will transmit 450hp at 260cm diameter. 

Ø      In practice we have established that the –29 blade gives significantly enhanced performance over the –27 blade even with 360-hp.  Depending on the performance parameter, this ranges from +2% to +13%.

Ø      Finally, in terms of choices, MT offers a standard and also a ‘large’ spinner for this propeller.

Ø      (We have a separate information sheet on MTV propellers for Sukhoi and Yak aircraft).

Warranty

We warranty all the engines that we sell on the following basis:

Ø      New engines are warranted for one year or one hundred hours from the date of installation.  

Ø      Overhauled engines are warranted for six months or fifty hours from the date of installation.

Ø   The installation of an engine must occur within three years of delivery.

Ø The warranty applies to the original purchaser of the engine and is not transferable without our formal agreement.

We will, however, consider problems that occur outside these formal warranty periods.

The warranty is restricted to replacement of the failed component or subassembly, or even engine if relevant, but not for any costs of actual replacement or any consequential losses – (i.e. cost of hiring other aircraft etc).