Monday, March 29, 2010


So recently, AC313 made its maiden flight. As previously known, it is just an improved civilian version of the Z-8 series, which is basically Chinese version of SA-321, first purchased from the French in the 80s. In fact, the internal designation of AC313 is Z-8F-100 as shown in one of the pictures I've attached. Below is the translation of an article on AC313.

AC313 is China's first large transport helicopter designed accoring to flight regulation and China's only only self designed/produced larger helicopter. It fills a vacuum in the large civilian helicopter segment. AC313 is a traditional single-rotor helicopter with tail rotor tandem pilot seating, carries 3 turboshaft engine and non-retractable landing gear. It's maximum starting weight is 13.8 ton and is suitable for use in ocean climate and other complex environmental condition. It can takeoff and land in most field type. It can be used to transport people and goods, do search & rescue, perform emergency rescue and disaster relief.

Rotor system uses advanced composite material for blade and titanium ball shaped main rotor. Composite material is used on 50% of the helicopter and titanium is used for the remainder. The avionics system uses the international standard's 429 databaus, achieving digital integrated display control. AC313 reaches 3rd generation level interionally and has the following safety requirements:
- The rotor system can achieve 30 minutes of dry rotation
- fuel system and fuselage structure satisfy crash and radar safety requirements.
- pilot and passenger seating passed anti-crash safety requirements
- fuselage structure, flight control sytem and rotary wing system satisfies bird collision requirement
- helicopter systems satisfy lightning strike and high-strength radiation protection requirement
- cabin setup satisfies requirement of passengers getting out in emergency situations
- rotor and composite material structure meet the fatigue assessment based on damage tolerance requirements
- Mechanical systems satisfies the design requirements of high-energy rotor burst protection

AC313 uses composite material for rotor system and FADEC engine, large usage of composite material, integrated avionics systems, digital design and newest airworthiness safety requirement. It allows China to jump from 2nd to 3rd generation in large transport helicopter technology. Due to emphasis in maintenance detail design, service life reliability design and design, AC313's service life usage economics has improvement over previous models.
AC313 has 7 special achievement in functionality.
1. High reliability. It has 3 engines and can still operate if one of the engines fails and can land when 2 engines fail.
2. Strictly follows fungal protection, heat/humidity protection and salt fog protection. Is suitable to use in ocean condition and other harzaradous environment
3. Large space. Cabin is 1.83 m and 23.5 m^3 in space. And average height Chinese person can walk in it standing up. Has comfortable seating and interior. Can be converted to VIP variant.
4. Can carry 4 tonne of inside the helicopter or 5 tonnes on a sling. Can carry a maximum of 27 passengers or 15 stretchers with one medical personnel seating and operational station. Can easily install fixed cargo.
5. Has long range. 900 km with full internal fuel and has ferry range of over 1400 km when carrying 3 fuel tanks.
6. Has excellent sterring system, combined with four-axis autopilot, operating load is small, good flying qualities.
7. Can be used in evironment from -40 to +50 celsius. Can fly an altitude of 6000 m and takeoff and land at 4500 m high airpot.
AC313's well designed aerodynamics, advanced rotor system, rotor system's low stalling rate, tail rotor's strong ability against side wind have pushed Chinese large transport helicopter past technological bottlenecks. Has ability to fly in highland, mountainous regions and other complex geographical regions.

Here are some of the photos showing the cockpit of AC-313, test flights and registration:

So, it is clearly a heavily modified version of Z-8. Unfortunately at the moment, AVIC-1 is still stuck in the stage of co-developing helicopter with more advanced helicopter companies or modifying Z-8/9/11s. After years of struggling with Z-8 production, they have at least managed to crank up production of this series. As seen with Z-8F, AC-313 should at least get some orders from Chinese companies for different roles like firefighting, transport and SAR missions. I also think it will eventually be adapted for the navy to be used on future carriers or LPDs. It could also be used by the army for SAR or transport roles (like with Z-8Ks). If that's the case, then they would have to eventually develop domestic engines to put on militarized AC-313. Either way, if AC-313 does reach the designed specs, it will be a step forward for the Chinese helicopter industry. Just as important, if the production rate of AC-313 can satisfy both civilian and military demand, it would also be a step forward for the Chinese helicopter industry which produced less than 3 Z-8s a year for much of the 90s and early 2000s.

Interestingly enough, we also saw a new version (or one modified from existing Z-8Js) of Z-8 carrying gun pod.

It is most likely carrying QJK-99, which is sometimes seen carried on Z-9s. Here is a link on QJK-99 in Chinese. This version of Z-8 gunship could be fielded on 071 in the future. It's certainly a development worth keeping our eyes out for.

We've also seen Z-8KH join service in Hong Kong. So, we are continuing to see a lot of projects involving this old platform, which is now about to get a new facelift.


SINOGASS said...

Every progress is a victory to close the gap...

timurelame said...

Any news about the PLA 10-ton helicopter project?