What's new

Naval Helicopter ALH Dhruv Gets Foldable Rotors

Techy

FULL MEMBER
Joined
Apr 18, 2015
Messages
222
Reaction score
5
Country
United States
Location
India
Indian_Navy_Dhruv_1.jpg


Naval versions of India’s ‘Dhruv’ Advanced Light Helicopter (ALH) will get folding rotors to accommodate the chopper in tight spaces on board Indian ships.

Work on this modification has been done at Hindustan Aeronautics Limited (HAL) in Bangalore to make the rotors foldable which will increase the versatility of the helicopter. The Naval ALH Dhruv is currently used as search and rescue (SAR) helicopter which means it has to land on ships’ helicopter platforms, aircraft carriers and be stowed away in narrow spaces.

While the Indian Navy was happy with versatility of the 5.5 helicopter, a problem with the Dhruv was that its rotors did not fold to be fitted on smaller decks of offshore patrol vessels or even frigates of the class of INS Talwar.
The problem was raised by the Indian Navy about six months ago. A source in HAL said, “the problem has been sorted out. HAL representatives visited the naval installation in Vizag and demonstrated these changes that have been made about the foldability of the rotors.”

A navy source says that more than a dozen ALH have been asked to make the rotors foldable and are awaiting delivery. The problem of the Dhruv rotor is that two of its rotors did not fold the way the Indian Navy’s older helicopters such as the Chetaks or Sea Kings did on deck.

But now HAL has cracked the problem. Two of the Dhruv’s rotors fold into the body of the aircraft, while one remains straight outward.

Source>>
 
Dhruv is changing Indian helicopter context slowly but significantly. Dhruv's portfolio is expanding and now with a foldable naval version its importance across all OPVs, Frigates and other forces are becoming more important.
Dhruv/ALH and LCH are one of the prized assets of India.
Wish they could make and test a bigger helicopter in the lines of Dhruv with somewhat similar concept to S70s... That could really change the context of our rotor wing assets even more..
 
Indian_Navy_Dhruv_1.jpg


Naval versions of India’s ‘Dhruv’ Advanced Light Helicopter (ALH) will get folding rotors to accommodate the chopper in tight spaces on board Indian ships.

Work on this modification has been done at Hindustan Aeronautics Limited (HAL) in Bangalore to make the rotors foldable which will increase the versatility of the helicopter. The Naval ALH Dhruv is currently used as search and rescue (SAR) helicopter which means it has to land on ships’ helicopter platforms, aircraft carriers and be stowed away in narrow spaces.

While the Indian Navy was happy with versatility of the 5.5 helicopter, a problem with the Dhruv was that its rotors did not fold to be fitted on smaller decks of offshore patrol vessels or even frigates of the class of INS Talwar.
The problem was raised by the Indian Navy about six months ago. A source in HAL said, “the problem has been sorted out. HAL representatives visited the naval installation in Vizag and demonstrated these changes that have been made about the foldability of the rotors.”

A navy source says that more than a dozen ALH have been asked to make the rotors foldable and are awaiting delivery. The problem of the Dhruv rotor is that two of its rotors did not fold the way the Indian Navy’s older helicopters such as the Chetaks or Sea Kings did on deck.

But now HAL has cracked the problem. Two of the Dhruv’s rotors fold into the body of the aircraft, while one remains straight outward.

Source>>

Won't take much effort since HAL has already developed it for the LUH which also automatic blade folding mechanism. But still to automatic blade folding comes with a weight penalty of about 100 kgs for naval ALH's.

IZ3A2178.jpg

aleAHF1.jpg

Will be interesting to see if even LUH has a naval variant or not.

21f.gif



It has it already?

An automatic system?

I guess those are segmented blades with manual folding mechanism instead - Naval Dhruv's segmented blades comprise of two blade parts. The outer part is folded inwards to obtain the desired folded width. It is 5.1 metres wide instead of the navy’s requirement of 3.5 metres.
 
Indian_Navy_Dhruv_1.jpg


Naval versions of India’s ‘Dhruv’ Advanced Light Helicopter (ALH) will get folding rotors to accommodate the chopper in tight spaces on board Indian ships.

Work on this modification has been done at Hindustan Aeronautics Limited (HAL) in Bangalore to make the rotors foldable which will increase the versatility of the helicopter. The Naval ALH Dhruv is currently used as search and rescue (SAR) helicopter which means it has to land on ships’ helicopter platforms, aircraft carriers and be stowed away in narrow spaces.

While the Indian Navy was happy with versatility of the 5.5 helicopter, a problem with the Dhruv was that its rotors did not fold to be fitted on smaller decks of offshore patrol vessels or even frigates of the class of INS Talwar.
The problem was raised by the Indian Navy about six months ago. A source in HAL said, “the problem has been sorted out. HAL representatives visited the naval installation in Vizag and demonstrated these changes that have been made about the foldability of the rotors.”

A navy source says that more than a dozen ALH have been asked to make the rotors foldable and are awaiting delivery. The problem of the Dhruv rotor is that two of its rotors did not fold the way the Indian Navy’s older helicopters such as the Chetaks or Sea Kings did on deck.

But now HAL has cracked the problem. Two of the Dhruv’s rotors fold into the body of the aircraft, while one remains straight outward.

Source>>

Hope they replace the chetaks with this
 
A good development indeed, though the title can be a bit misleading. Dhruv already had manual foldable rotors , this one has got a automatic folding mechanism I guess. Automatic folding mechanism in case of hingeless rotor designs isn't easy.
 
About 32 of them were ordered for the Navy and Coast Guard last year. Can anyone tell about the status of it?
 
Now easier to park them in frigates and destroyers
 
Something is better than nothing but even we have Dhruv It is something which is better than many thing and in many context . We still got a long way to go
 
Real achievement would be when we are able to include ASW in naval Dhruv, it may be very limited but what we need is a beginning.
 
Real achievement would be when we are able to include ASW in naval Dhruv, it may be very limited but what we need is a beginning.

They might not be dedicated for ASW roles but ALH-WSI/Mark III has demonstrated some of it in the past - though the proposed dedicated anti-submarine warfare (ASW) variant was deemed unsuitable by the Navy, which was reportedly dissatisfied with the folding blade performance, maintenance record and endurance issues with full payload capacity at sea.

1-710478.JPG
2-711322.JPG
3-712083.JPG

Dated photos from HAL of the ALH Dhruv Navy conducting air-launched torpedo tests off Visakhapatnam.

Hope they replace the chetaks with this

The problem with Naval ALH is that the 5.5 tonne dhruv fall between two stools. it is too large and heavy to perform the role (search & rescue, communications, etc) that 3-tonne helos like the cheetah and the chetak currently do and too small and light to replace 10-14 tonne helos like the sea king and the kamov. And that's the reason why the Navy is not replacing it's Chetaks/Cheetahs with ALH's and neither has it placed a big order for the same.
 
They might not be dedicated for ASW roles but ALH-WSI/Mark III has demonstrated some of it in the past - though the proposed dedicated anti-submarine warfare (ASW) variant was deemed unsuitable by the Navy, which was reportedly dissatisfied with the folding blade performance, maintenance record and endurance issues with full payload capacity at sea.

1-710478.JPG
2-711322.JPG
3-712083.JPG

Dated photos from HAL of the ALH Dhruv Navy conducting air-launched torpedo tests off Visakhapatnam.



The problem with Naval ALH is that the 5.5 tonne dhruv fall between two stools. it is too large and heavy to perform the role (search & rescue, communications, etc) that 3-tonne helos like the cheetah and the chetak currently do and too small and light to replace 10-14 tonne helos like the sea king and the kamov. And that's the reason why the Navy is not replacing it's Chetaks/Cheetahs with ALH's and neither has it placed a big order for the same.

Well then,let's hope they replace the chetaks with homemade LUH
 
Back
Top Bottom