Hip or Hind Helicopters for the AFP?

An Mi-35 Hind Helicopter of the Czech Air Force. Photo courtesy of Wikimedia Commons.

In his speech during the 48th Anniversary of the 250th Presidential Airlift Wing last September 2016, the new President Rodrigo Duterte dropped a bombshell and possible major shift in the policy of the Armed Forces of the Philippines (AFP) when he revealed that he had received offers with generous financial terms from Russia to provide us with weapons and military equipment. He then said that he will be sending personnel from the Department of National Defense (DND) to go there and explore these options.¹

A couple of weeks later, a supposed insider from the Department of Foreign Affairs (DFA) revealed anonymously to “The Manila Standard” news publication that the government is reportedly considering the purchase of two to four Mi-17 or Mi-24 Helicopters from Russia for the price of between USD 12 to 17 million each.² This is a very interesting report because if it does push thru, it will be the first major military equipment buy by the Philippines from Russia.

’Hips and Hinds’
Both the Mi-17 and Mi-24 are made by the Russian Helicopter manufacturer, “Mil Moscow Helicopter Plant”. Both also have a common lineage in that they were developed from the Mi-8 Medium Lift Transport Helicopter which first entered service with the then Soviet Union in 1961.

The Mi-17 is an improved export version of the basic Mi-8 with more powerful engines and strengthened fuselage that allows it to carry heavier loads. It is mainly a Transport Helicopter that can also be configured for the attack role. It was first exported to other armed forces in 1977 and has the North Atlantic Treaty Organization (NATO) code name of “Hip”, the same as that of the Mi-8.³

The Mi-24 on the other hand is a specialized version of the Mi-8 built for the Attack role. For that its front fuselage has been heavily modified to house tandem (i.e., one behind the other) seat cockpits with bubble canopies, small wings and turreted weapons and sensors. The Mi-24 first entered service with the Soviet Union in 1972, and was given the NATO code name of “Hind”.

The Mi-24 is actually the Russian designation of the Hind, and since then they have modernized and come up with a new designation for the export version of it which is the “Mi-35”.⁴ So if we are really getting Hinds, it will be the Mi-35 and not the Mi-24.

These two aircraft are some of the most commercially successful military helicopters in the world, in service with over 100 countries and with well over 10,000 units estimated to have been built between them. If successful, these will be the biggest helicopters ever in our inventory with a Maximum Take Off Weight (MTOW) of around 13,000 kg, which is twice as heavy as our W-3 Sokol helicopters and four times as heavy as our AW109 helicopters.

’The Mi-17 for Transport’
Both our Air Force and Navy have requirements for Medium Lift Helicopters (MLH), but our Navy’s requirements seems to be for a smaller MLH than that of the Mi-17 because their Tarlac-class Landing Platform Docks (LPD) can only carry one helicopter with a maximum weight of ten tons in its hangar, and two more such helicopters in the Landing Pads.

The dimensions of these helicopters were also specified to be that of the smaller UH-60 Blackhawk helicopter.⁵ A single Mi-17 can still land and take off from the Tarlac’s two Landing Pads, but that’s it, the Tarlacs won’t be able to house them in the hangar.

Of course our Air Force could still opt for a bigger and heavier MLH, but there are logistical advantages also if the branches of our armed forces use the same aircraft, like in the case of the AW109 helicopters when both the Navy and Air Force bought and used them at about the same time.

However, if the Air Force does get a larger MLH like the Mi-17 instead, then that would be huge boost in their Helicopter Airlift capability since each Mi-17 can carry around 36 passengers, three times that of our UH-1 Huey or W-3 Sokol helicopters and around six times that of our AW109s.

’The Mi-17 for COIN’
The Mi-17 can have a secondary role as an Attack Helicopter and it can carry the same weight of weapons as the Hind externally, but it won’t have the Mi-35’s gimballed Guns, and it's cockpit won’t have the same field of view as the Mi-35’s bubble canopies. A bigger concern for me though is its huge size which makes it an easier target to hit from the ground.

I have seen the W-3 and AW109 up close personally side by side during the 2016 Balloon Festival at Clark, and my first impression then was just how big the W-3 is compared to the AW109. And that was just the W-3, which is only half the weight of that of the Mi-17, so just imagine how much bigger the Mi-17 would be.

The Mi-17 does have armor, but it is not as good or as extensive as that of the Mi-35 as it needs to allocate most of its weight to carry passengers and/or cargo. There are a couple of companies out there that are offering to add more armor to the Mi-17,⁶ but these add costs and weight and reduce the number of passengers/cargo that can be carried. And in the end, they still won’t make the Mi-17 as well protected as the Hind.

’The Mi-35’
The Hind is not just an ordinary helicopter, it is a Pop Icon, present in most major war movies made by Hollywood involving the Soviets or Russians since the 1980s, like the “Rambo” series of films, for example. It is a good aircraft to consider for our use in Counter-Insurgency (COIN) operations because of its ability to carry a large payload of external armaments, which I estimate to be at around 1,600 kg at full internal fuel.

This is three times that of our MD-520MG and more than twice that of our AW109 helicopters. Heck, it has about the same external payload as that of our OV-10 Broncos, or the A-29 Super Tucanos. Its turreted Guns are also a major advantage in terms of directing them effectively at anything around and below the helicopter. Like the Mi-17 it is a pretty large target also, but it has much, much better armor and armor coverage making it a lot more survivable.

For example, its Rotor Blades and Fuselage are designed to withstand hits from up to .50 cal. ammunition; It has a “Titanium Bathtub” around the Cockpits which is able to resist ammunition as large as 20 mm caliber; and its front windscreens are also able to withstand up to 20 mm caliber ammo.⁷ Based on these, the only weapons that can reliably bring down a Hind are cannons above 20 mm caliber, or Man-Portable Air Defense Systems (MANPADS).

The Hind can also carry passengers, and while it is a great COIN aircraft, as a Transport aircraft it is only mediocre as it carries only eight passengers, which is only slightly more than the AW109 and less than that of the W-3, and only about a fifth as that of the Mi-17.

’Mi-17 Evaluation Findings’
The American defense research institute “Research and Development (RAND) Corporation” did a very extensive (and not as easy to understand or absorb) evaluation comparing both helicopters to their western counterparts.⁸ One of their findings was that the Mi-17 was about as effective as most western made helicopters in terms of “Lift Effectiveness”, or the ability to complete its missions under various distance and altitude combinations.

They did find an issue with the Mi-17 in terms of “Lift Capability” in that it was unable to perform “Over Ground Effect (OGE)” hover at altitudes of more than 1,800 m. OGE means the ability of a helicopter to hover with no hard surfaces near enough below it for its downwash to react against,⁹ and this is critical on some missions like delivering external payloads, or hoisting people up or down during rescue missions.

At higher altitudes, the air density is thinner, thus there is less air for the helicopter’s rotors to work against. Now our mountains here are only about half the height of the Middle Eastern countries where the evaluation was set, but our highest peak, Mount Apo at around 3,000 m high is still above the altitude band where the Mi-17 performed best.

However, note that a lot of the other western helicopters like the UH-1 Huey, Bell 412 and AW109 which we are operating were also found to have the same OGE problems at high altitudes in the evaluation, but that does not seem to have affected our Air Force's operations too much so far.

In terms of “Cost-Effectiveness” in completing missions with different Distance-Altitude combinations, the Mi-17 was found to be generally either as cost -effective or more cost-effective than most western made helicopters. The only helicopter that was able to beat it consistently in that and other criterias was the CH-47 Chinook, which is a much bigger and more expensive helicopter.

’Mi-35 Issues’
The Mi-35 on the other hand didn’t do as well in the evaluation. In terms of “Attack Aircraft Effectiveness”, for example, the Mi-35 was only able to conduct consistently at least 15 minutes of Loiter Time at the combination of below 1,800 m altitude and less than 160 km range.

In that regard the Mi-17 managed to beat the Mi-35 in the attack role as it was able to do so at higher altitudes and longer ranges. The Mi-35 also performed poorly in terms of “Cost-Effectiveness”, again only being competitive at altitudes below 1,800 m and ranges of less than 160 km.

'VK-2500 Engine Option'
A more serious issue for both aircraft is the low Time Between Overhaul (TBO) of its TV3-117VM engines which is only 1,500 hours. This compares poorly with western made helicopters which has much higher TBO schedules, like the PW206 engines of the AW109 helicopters, for example, whose TBO is almost three times that at 4,000 hours.¹⁰

However, the Mi-17 and Mi-35 helicopters does have the option of using the VK-2500 engine which has a higher TBO of 3,000 hours,¹¹ which compares better to the standard TBO of western helicopters.

As a bonus, the VK-2500 is also more powerful by around 600 HP, making it better suited for high altitude conditions and may solve the OGE issues of the Mi-17 at altitudes above 1,800 m. It is the same engine that Venezuela used on their Mi-17s for their mountain operations.¹² Hence if we are getting the Mi-17 or Mi-35, we should look into getting the VK-2500 if we can rather than the TV3-117VM engines, although it is likely to be more expensive.

’Parting Shot’
As a Transport helicopter, the Hip does very well compared to most western helicopters in terms of Lift and Cost
Effectiveness in most missions. In the attack role, it does not have the kind of weapons and armor that the Hind has, but does better in terms of performance and cost. It may be too big for our Navy, but would be very good for our Air Force, especially if the VK-2500 engine does solve its OGE issues at high altitudes.

The Hind has great weapons and armor for COIN operations, but works best in terms of performance and cost under low altitudes and short ranges. Like the Hip it seems to be too big for our Navy, but could do well with our Air Force if they think its weaknesses are not as critical or that it would still be good compromise despite it.

Between the two, the Hind is by far the more glamourous option. However, personally for me I tend to like the Hip a little bit better now since it has better overall performance and can do more missions. As for it being a large target and having lesser armor for COIN operations, that could be offset by having it fly at higher altitudes to make it less vulnerable to small arms fire, and arming it with longer ranged weapons so it can still reach its targets.

At any rate, whether we get the Hip and/or the Hind, either helicopter will offer a significant improvement in capability over the helicopters we are using now. So I wish the Russians udachi (good luck), I hope they make it.

An Mi-17 Hip Helicopter of the Afghan Army Air Corps. Photo courtesy of Wikimedia Commons.

SOURCES:

1. Duterte: PH to buy defense assets from Russia, China,(https://web.archive.org/web/20161017233539/http://www.rappler.com/nation/146155-duterte-defense-assets-russia-china)
2. Manila, Moscow near deal on $12-m choppers,(https://web.archive.org/web/20161007191839/http://thestandard.com.ph/news/-main-stories/top-stories/218191/manila-moscow-near-deal-on-12-m-choppers.html)
3. Mi-8/Mi-7 Transport and Passenger Helicopter,(https://web.archive.org/web/20160422005955/http://www.russianhelicopters.aero/en/helicopters/military/mi-817.html)
4. Mi-35M Attack Helicopter,(https://web.archive.org/web/20161023180314/http://www.russianhelicopters.aero/en/helicopters/military/mi-35m.html)
5. Strategic Sealift Vessel (SSV) Supplemental Bid Bulletin (SBB) - August 23, 2013,(https://web.archive.org/web/20161029062643/https://rhk111smilitaryandarmspage.files.wordpress.com/2016/10/2013-08-13_ssv_sbb.pdf)
6. Armor set for Mi-17 Helicopter,(https://web.archive.org/web/20161028092315/http://www.asubaltija.lt/specs/0000/0051/armor-web.pdf)
7. Mi-24 HIND: The Flying Russian Crocodile Can Fight and Flee,(https://web.archive.org/web/20160828140853/http://gizmodo.com/mi-24-hind-the-flying-russian-crocodile-can-fight-and-507543530)
8. Cost-Effective Helicopter Options for Partner Nations,(https://web.archive.org/web/20160721073541/http://www.rand.org/content/dam/rand/pubs/research_reports/RR100/RR141z1/RAND_RR141z1.pdf)
9. IGE, OGE and Recirculation,(https://web.archive.org/web/20160131135111/http://www.helis.com/howflies/igeoge.php)
10. P&WC Announces PW200 TBO Extension,(https://web.archive.org/web/20161101002601/http://www.ainonline.com/aviation-news/2013-03-05/pwc-announces-pw200-tbo-extension)
11. Reworking a classic,(https://web.archive.org/web/20160513052724/http://www.russianhelicopters.aero/en/press/publications/5064.html)
12. Venezuela to get Russian helicopters with VK-2500 Altitude Engines,(https://web.archive.org/web/20161028092615/http://www.oboronprom.ru/en/news/venezuela-get-russian-helicopters-vk-2500-altitude-engines)