[Jeroen]

A few weeks ago I got an invite from one of my Oldtimer clubs (https://www.oldtimerclubfriendsandoldtimers.nl) to join them for a special visit to the one and only Dutch Alouette helicopter museum in Barneveld.

I must be honest, I had never ever heard of this museum before. But I do know the Alouette. I have actually flown in one, many decades ago. So I signed up obviously. What better way to spend a Saturday to drive to an aviation museum in one of your oldtimers? Spoiler alert: It was absolutely worth it, great day. Learned lots about the Alouette and met some interesting folks as well.

Of course, the Alouette is no stranger to the Indian Airspace either. And I will come back to that later.

Because this is a small museum the number of participants was limited. Also, the club had arranged from them to tow one of the Alouette outside so each member could have an image take of his/her oldtimer with the beautiful helicopter. Here my 40 year old Mercedes W123 next to an even older Alouette!



But as this is a car forum, let me share a few images about the cars in which our members turned up. Getting to the museum was not that difficult. Although, it is not really sign posted and is located at a small industrial estate, there is sort of a give away on one of the buildings, something aviation like is going on here!!!



Some of the oldtimers that showed up:







Not really an oldtimer, not even a young timer, but still an incredible cool car. If I was to buy a new car, I would like to think I would get myself a Renault Alpine!



Lets talk a little bit about the Alouette. We will be talking and seeing mainly the Alouette III.

From Wikipedia:

The Aérospatiale Alouette III (French pronunciation: ​[aloo-wɛt], Lark; company designations SA 316 and SA 319) is a single-engine, light utility helicopter developed by French aircraft company Sud Aviation. During its production life, it proved to be a relatively popular rotorcraft; including multiple licensed manufacturers, more than 2,000 units were built.

The Alouette III was developed as an enlarged derivative of the earlier and highly successful Alouette II. Sharing many elements with its predecessor while offering an extra pair of seats and other refinements, it quickly became a commercial success amongst both civil and military customers. Further variants were also developed; amongst these was a high-altitude derivative, designated as the SA 315B Lama, which entered operational service during July 1971. The Alouette III was principally manufactured by Aérospatiale; the type was also built under licence by Hindustan Aeronautics Limited (HAL) in India as the HAL Chetak, by Industria Aeronautică Română (IAR) in Romania as the IAR 316 and F+W Emmen in Switzerland.

Similar to the Alouette II, in military service, it was used to perform missions such as aerial observation, photography, air-sea rescue, liaison, transport and training; it could also be armed with anti-tank missiles, anti-shipping torpedoes, and a fixed cannon. In a civilian capacity, the Alouette III was commonly used for casualty evacuation (often fitted with a pair of external stretcher panniers), crop-spraying, personnel transportation, and for carrying external loads. By the 2010s, many operators were in the process of drawing down their fleets and replacing them with more modern types; the French military intend to replace their Alouette IIIs with the newly developed Airbus Helicopters H160.[1

Anorak fact: check out this Wikipedia page on the Alouette III. It has an image of one of the Dutch Airforce Alouette’s during a flight display.

From Wikipedia:


The Alouette was a very successful design. It saw service in over 45 different airforces and a few civilian carriers. It was produced for more than 20 years, the last one being produced in 1985. More than 2000 of these helicopters were build, in various places in the world. Some of these wonderful machines were still flying in 2015!

The Dutch Airforce had 77 Alouette’s and they have been in service for fifty years!
The people behind the museum were interested to research, document and preserve the Dutch Airforce Alouette history. All of the Dutch Airforce Alouette’s at some point disappeared abroad. The museum managed to bring seven of these original Dutch Alouette back to the Netherlands and have been restoring them since.

Here you have the main characteristics of the Alouette III:



The Dutch Airforce Alouette’s were only suitable for VFR flight (Visual Flight Rules). I don’t know if any Alouette’s were ever certified for IFR (Instrument Flight Rules), but probably not. When the Alouette first came out, flying helicopters in the dark, with poor or no visibillity was not something anbody would contemplate. These days of course, many helicopters are fully IFR certified.

Lets have a bit of close up look:



This particular one has some sort of camera mounted:





Controls of the camera



Cockpit instruments



The business end, a very complicated looking rotor



This particular Alouette, the 208 was found at a museum in Gothenburg, Sweden. (https://aeroseum.se/history-and-background/)
The Dutch 208 somehow ended up in Sweden where it was certified for civilian use. There is a big network between the various aviation museums when it comes to exchange parts and planes. In this particular case, the Dutch Alouette museum provided two crates full of parts to the Aeroseum in exchange for the 208 and others. Volunteers of the Dutch museum are helping their Swedish colleagues with restoring the remaining Alouette in Sweden.

Here another one of the lovingly restored Dutch Alouette



This particular one was found in Switzerland. It had been totalled during a nose landing. It was brought back to the Netherlands where it has been fully restored to its former glory.

A not very good image of the photograph showing the damage due to the hard nose landing.



A few more details of the cockpit. Very simple and basic.





I noticed these little graphs stuck to the top of the instruments on some of the Alouette’s.



It depicts the correlation between collective pitch and tailpipe temperature. The jet turbine gets loaded up most during hoovers and vertical climbs, the outlet temperature, or tailpipe temperature is an important parameter to monitor.

One of the volunteers used to work as an instructor and mechanic on these machines. I had a long chat with him. Overall these Alouette were very reliable. The jet turbine was very reliable. Probably because it was a bit overrated, which meant in practice it rarely ran at more than 70% of its max rating.



If there was ever any doubt that this is a French design have a look at the fuel cap:



This is just a little museum with one main area. But it is cramped full of stuff about or from the Alouette. Just a few images of bits and pieces on display.





The (expired) certificates of registration and airworthiness







The Alouette has been used for VIP transportation as well. Here you see it picking up former Dutch queen Beatrix.

[Jeroen]

Lets have a look at the Alouette Indian connection. I am sure some of our far more knowledgeable members than me will chip in. I have found a few things on the internet:

From Wikipedia:

Despite the closure of Aérospatiale 's own production line, the event was not the end of the type's manufacturing activity. Over 500 Alouette IIIs are recorded as having been manufactured under licence abroad in several countries, such as Romania, India, and Switzerland.[8] Hindustan Aeronautics Limited (HAL) obtained a licence to construct the Alouette III, which was known locally as the HAL Chetak, at their own production facilities in India.[8] More than 300 units were built by HAL; the company has continued to independently update and indigenise the helicopter over the decades. A modernised variant of the Chetak has remained production, though at a diminished volume, into the 21st century. Various versions of the Alouette III were also either licence-built or otherwise assembled by IAR in Romania (as the IAR 316), F+W Emmen (de) in Switzerland, and by Fokker and Lichtwerk in the Netherlands

Under a licensing arrangement between Aérospatiale and Indian aircraft manufacturer Hindustan Aeronautics Limited (HAL), the Alouette III has been built under licence by HAL in India. Known locally under the designation HAL Chetak, more than 300 rotorcraft have been manufactured to date; the majority of these were acquired for military purposes with the Indian Armed Forces, who have used them to perform various mission roles, including training, transport, CASEVAC (casualty evacuation), communications and liaison roles.[26] By 2017, the Chetak was reportedly serving as the most widely used IAF helicopter for training, light utility and light attack roles.[27]

During 1986, the Indian Government constituted the Army's Aviation Corps; consequently, the majority of Chetaks previously operated by AOP Squadrons were transferred from the Indian Air Force to the Indian Army on 1 November 1986. The Air Force has continued to fly a force of armed Chetaks in the anti-tank role as well as for CASEVAC missions and general duties. During the 2010s, the Chetak is being gradually replaced by the newer HAL Dhruv in the armed forces.[26] An option to re-engine the HAL Chetak with the Turbomeca TM 333-2B engine, which would better facilitate high-altitude operations in the Himalayas was considered, but ultimately not pursued.[citation needed]

In addition to producing the type for Indian customers, HAL has also achieved some export sales of Chetak helicopters to several nations, including Namibia and Suriname.[28] India has also opted to donate several secondhand Chetak helicopters to other countries, such as neighbouring Nepal.[29] As of 2017, the Indian Navy has reportedly recognised the necessity of procuring a replacement for the type.[30]

HAL Chetak was used in Operation Khukri which was a multinational operation launched in the United Nations Assistance Mission in Sierra Leone (UNAMSIL), involving India, Ghana, Britain and Nigeria .[31]

Beginning in the 1970s, during Republic Day parades, Chetak helicopters have been decorated to look like animals such as dodo birds, fish, and, most notably, elephants. The helicopters decorated like elephants have become iconic in India, and known as names such as "dancing elephant helicopters" and "flying elephants".

I found this image on the Indian army webpage (https://indianarmy.nic.in/Site/FormT...I2M1EQXinM4A==)



Being a pilot and an engineer I love talking to the volunteers at these sort of museum. They are often ex army and used to fly and or work on these machines.

Here a couple of interesting facts I learned about the Alouette.

The rotor has three blades. Inside of the blades there are little balancing weights that can be adjusted/moved. The blades need to be perfectly balanced. They used to have a huge balancing machine. Initially blades were balanced and also replaced three (complete set). Later with more modern production techniques rotor blades were balanced and replaced individually. But so I was told, by then the price of a single blade was about the same as the price of the original set of three. So there is progress for you.

Apart from the balancing it is very important that the three blades spin in exactly the same horizontal plane. What they used to do is put some different colour marking on each tip of the three blades.



Next they would spin the rotor slowly across a vertical pole. The tips would just touch the pole. With three different colours they could adjust each blade to run perfect.

The blades are made of aluminium and are filled with a sort of pur-foam.



During one of its missions an Alouette was hit by small arm fire. This is what it does to the rotor blade.

Entry


Part exit


I always find the rotor of any helicopter a fascinating piece of engineering. The movement of the blades are carefully controlled in different directions. Obviously there is the speed at which the rotor spins. The collective lever controls the pitch,
But they can also move up and down (flap) and move forward/backward (lead or lag)

There are three main different rotor systems. If you want to know a bit more have a look at this little video.

https://www.youtube.com/watch?v=a354_CJI-m0

The Alouette has a fully articulated rotor system.



The cables you see are known as spacing cables. As the rotor blades spins each blade, depending on its position, will slow down a bit or accelerate a bit compared to the other blades. Here you also see the so called drag dampers that assist in reducing that effect. The cables will keep the blades separated in case anything goes wrong with the dampers.

In general the fully articulated rotors give a smooth ride, but they are complex to maintain.



A close up look at the tail rotor:





The tail rotor is driven by means of shaft of the jet turbine. It has adjustable pitch. You can see the drive mechanism of the pitch here. Those wire on that drum are connected to the foot pedals in the cockpit.

The Alouette saw extensive action during its operational time with the Dutch Airforce. There are a number of posters on the wall, depicting the various operating theatres they were involved in.





These rotor blades used to hang on the wall of various Airforce operation rooms or mess rooms.



When squadron members from one squadron visited another squadron it was customary to leave a sticker on these blades. Looks like there was a bit of rivalry between 313 and 315 squadron!



All of the museums Alouette’s are original Dutch military registration. It would be great to be able to put them on a civilian registration and get them airworthy again. However, in order to do so, you need to be able to comply with many many regulations. For instance you need to be able to have a proper maintenance organisation and facility. That is just beyond what a small museum like this can do. Some of the helicopters are in running order and do get fired up occasionally. Also, you can rent these helicopters for event. They will get trucked to wherever you want them.

The Dutch Airforce flew these choppers for 50 years. From 1973 to 1995 they also had a Alouette demonstration team, The Grasshoppers.

This Youtube video is a demo given in 1979. Commentary is in Dutch I’m afraid. But have a look at how close the demo was to the public. Those were the days for aviation enthusiast.

https://www.youtube.com/watch?v=G2KXrW8jq-s

A couple of volunteers from the museum wanted to recreate the Grasshoppers. Obviously they could not do it with real Alouette’s, so they made their own Radio Controlled ones!!

https://www.youtube.com/watch?v=CW4Png5GClg

The RC helicopters are not on display in the museum as such. However, when I told them I would be writing an article for the Indian TeamBHP website I was allowed a behind the scene peek. Many thanks!!

The club has an awful lot of spare parts, mostly from the army. And they had to spend an awful long time cataloguing them and putting all the data into a computerised stock system.





Next to this warehouse is where the RC helicopters are kept. These are wonderful models.







Also, some models of the earlier version of the Alouette. Different canopy amongst others and open tail section.







By then the photograph of each members car had started and I found myself in my W123 behind the Renault Alpine, waiting for my turn.



Alouette and W123. Almost 100 years combined aviation and car history!!



A few more detailled shots of this gorgeous little helicopter.









On the 30th of July 2023 the museum will be celebrating that it has been 50 years since the Alouette Grasshopper team was formed by the Dutch airforce. Both the blue and red Alouette have been original Grasshopper helicopters. So there is going to be some interesting activities I will be on the lookout for.

All in all a fantastic day. Many thanks to the Oldtimerfriends club for organising this event. And many many thanks to all the museums volunteers for hosting this event and answering all my endless questions!

Jeroen

[Aditya]

Thread moved out from the Assembly Line. Thanks for sharing!

[V.Narayan]

Thank you Jeroen for yet one more aviation delight just as you had promised. That video on how a rotor works is good. It is an immensely complex piece of mechanical engineering. The Aloutte III SA316 and its close cousin Lama SA315, Chetak & Cheetah in India are still in full service in some countries mainly India even today 53 years after it entered French service in 1960. For our readers the world's absolute helicopter altitude record is held by Jean Boulet, a French test pilot, flying a SA315B at 40,814 feet. No one has ever come close. Where our license production went the French made it a real 101% license production rather than the more usual CKD assembly transfer.

Compared to modern helicopters today it was cheerfully uninsulated for noise or vibration!!! But those were different days. Alas I never had the opportunity to sit in one or fly in one as a piece of excited baggage.

Alouette III forever.

PS: Thank you for these excellent photos.

[Pennant1970]

The word "Alouette" brings back to me a rhyme I learnt a few year ago, while wrestling with learning French - “Alouette, gentille alouette, alouette je te plumerai” (lark, nice lark, lark I will pluck your feathers). A rather dark and gruesome way to teach children birds' body parts!

On the matter of choppers, for some reason, the Alouette 2 is the quintessential image of a helicopter - in my mind, anyway! Or am I thinking of the Lama 315 (that V Narayan mentioned above)? I am no aviator - but somehow, some nostalgic strings were touched when I saw the pics. Thanks.

[am1m]

Originally Posted by Pennant1970

I am no aviator - but somehow, some nostalgic strings were touched when I saw the pics.

Perhaps that's because this is most probably the model of chopper that Herge' based his drawings of a helicopter on, in one of the Tintin comics?

https://www.scoop.co.nz/stories/HL11...ie-is-made.htm

I don't know anything about helicopters either, but instantly remembered Tintin when I saw the pics on this thread.

[Jeroen]

Originally Posted by V.Narayan

For our readers the world's absolute helicopter altitude record is held by Jean Boulet, a French test pilot, flying a SA315B at 40,814 feet. No one has ever come close.

I have heard about that record. It’s hard to imagine you can get a chopper up to that altitude. Any details about the modifications they made to achieve this remarkable record?

Jeroen

[V.Narayan]

Originally Posted by Jeroen

I have heard about that record. It’s hard to imagine you can get a chopper up to that altitude. Any details about the modifications they made to achieve this remarkable record?

Jeroen

Flying Dutchman, your wish is my command. :-)


World altitude helicopter record

As mentioned in posts above French test pilot Jean Boulet, on 21st June, 1972, set the absolute world altitude record for a helicopter by climbing to 40, 820 feet {12,442 metres}over France. The helicopter was a temporarily lightened version of the SA 315 designed by Aerospatiale for the IAF – Lama in Europe, Cheetah in India. Otherwise, it was stock.

The SA 315B Lama was designed to perform at the very high altitudes and temperatures to meet IAF specs for a light helicopter to perform supply & recce duties in the Himalayas. The original specs were I think to carry 1 pilot and ~300 kgs of payload to ~20,000 feet. It combined an SE.3130 Alouette II airframe with a much more powerful Turboméca Astazou IIIB turboshaft engine—derated to 550 shaft horsepower, down from 870—and the rotor system, transmission and gearboxes from the larger 7-seater Alouette III.

The record-setting helicopter {shown below} was modified by removing all equipment that was not needed for the record flight attempt. Various instruments and the co-pilot and passengers seats were taken out of the cockpit, as well as the helicopter’s synchronized horizontal stabilizer and tail rotor guard. The standard fuel tank was replaced with a very small tank holding just 70 kilograms (approximately 22.7 gallons) of jet fuel. Turboméca modified the engine to increase the output shaft rpm by 6%. After Jean Boulet started the turbine engine, mechanics removed the battery and starter motor to decrease the weight even further. If on a fixed wing aircraft every extra kilo reduced is like gold then on a helicopter it is like platinum.

On crossing 40,800 feet when the helicopter could climb no higher*, Boulet reduced power and decreased collective pitch. The Turboméca engine, not calibrated for the very high altitude and cold temperature, -62°C, flamed out. With no battery and starter, a re-start was impossible!!! - talk of daring. Boulet put the Lama into autorotation for his 12 kms plus descent Entering multiple cloud layers, the Plexiglas bubble iced over. Because of the ice and clouds, the test pilot had no outside visibility. Attitude instruments had been removed to lighten the helicopter. Boulet looked up through the canopy at the light spot in the clouds created by the sun and used that for his only visual reference until he broke out of the clouds.

Still in autorotation, the SA 315 missed touching down exactly on its takeoff point,but was close enough that FAI requirements were met. The record stands unbroken. He also set records by chance for the longest descent in auto rotation.

Nerves of steel and what presence of mind. He was one of France’s top test pilots. He died in 2011 at age 90.

*Getting to that altitude was as much a factor of the pilot's skill and nursing the machine along as it was of the power to weight ratio.


Jean Boulet {1920 - 2011}. During WW-II he worked with the French Resistance and in 1945 went to USA to train to be a fighter pilot on the P-47 Republic Thunderbolts. Later he became the chief test pilot for SNCASE which morphed into Sud Aviation, then Aerospatiale, Eurocopters and is now called Airbus Helicopters.


On the day of his record breaking flight prior to kitting up, seated in the lightened SA315B


Jean Boulet coming into land on that fateful day while still in auto rotation less than a minute before touch down. Note the missing fuel tank under the rotor and missing tail guard. The machine was put back to stock condition and re-employed in commercial service in France till it suffered a crash in 1985.

I hope readers enjoyed this narration.

[KANNURAN]

Originally Posted by V.Narayan

For our readers the world's absolute helicopter altitude record is held by Jean Boulet, a French test pilot, flying a SA315B at 40,814 feet. No one has ever come close.

And Sir, equally impressive is Jean Boulet's UN-INTENDED record of autorotating the Lama to a safe landing from 40,818 feet, after the engine flamed out upon reducing power. Thats two records in one.

[Formula1]

Lama of course being a mashup of Alouette 2 and Alouette 3. There are a few other variants cooked up in India.

The little dragon fly should make a comeback with modern materials.

[Jeroen]

Originally Posted by V.Narayan

World altitude helicopter record

Thanks for sharing this wonderful and amazing story!

I can’t even begin to think how it must have felt to auto-rotate, with virtually no visibility all the way down!!

As KANNURAN mentioned, that feat in itself must be some record too.

Jeroen

[directinjection]

Lovely thread!

The helicopter was popularly known as the Chetak in India which was also the original name of the Indian Main Battle Tank later renamed "Arjun."

The Lama was known as Cheetah in India and a later, re-engined version of the same was known as Cheetal.

https://hal-india.co.in/Product_Deta...x%20passengers.

https://hal-india.co.in/Product_Deta...&lKey=&CKey=25

https://hal-india.co.in/Product_Deta...Reconnaissance


Aloutte III engine had a very distinctive, somewhat shrill sound. As a kid in Chandigarh in late 1970s/early 1980s, I could always identify a Chetak just by its sound! They flew over Chandigarh quite regularly.

The Lama/Cheetah often appeared in Hindi films of 1970s and 80s as the helicopter of the villain! In the end, the helicopter would inevitably be shown as crashing, engulfed in a ball of fire!

Here are two old Indian postage stamps showing the Chetak:

[shashanka]

A wonderful and informative write-up Jeroen. A helicopter's locomotion (rotor) system (fore and aft, athwartships and vertical motion) is as complex a bit of mechanical engineering as one could wish for! As a retired marine engineer it is always a pleasure to talk shop! The working principle of the helicopter's rotor is very similar (cycloidal pitch) to that of the Voith Schneider (

https://www.youtube.com/watch?v=Ub563Yc3xls

) vertical propeller fitted to many shallow draft tugs and off-shore craft, giving them astonishing maneuverability.

[shashanka]

Narainji, its always a pleasure to read your posts and threads on planes and the aviation sector. It was absorbing and inspiring too, to read about Jean Boulet's hair-raising exploit, and the fact that his record still stands.

[directinjection]

Came across this interesting video entitled "The Top Ten Helicopters of the World," in which the little Alouette (SA 315 Lama version) appears at 1:38.

https://fb.watch/jYSNyAxJtI/