The UH-1H Huey is an assembly of parts flying in formation. DCS: Huey, by Belsimtek, isn’t much different from its real-life counterpart. It can be stripped from a lot of parts and still be wobbling back to its base. Finally, the Huey most dangerous foe is its own pilot.
Bad approaches will lead to VRS. Repetitive hard maneuvers will just convince the rotor to divorce and live on his own. Overspeed will cause flight control trouble. Yet the community is asking for more suffering, and has been repeatedly asking for engine damage when overstressing the engine.
Let’s see what it is about!
How a Turbine Engine Works
The Huey is equipped with a single Lycoming T-53L-13B turboshaft engine. A gas turbine may look complex, but the principle is quite simple. The admitted air is first compressed. This is achieved by a set of rotating blades mounted on a shaft. It is the Compressor. The air will raise in pressure, but also his temperature. Then it reaches the Combustion Chamber. The jet-fuel is injected and ignited, raising even further the pressure and heat. This produce a large amount of energy, which then reach the third stage, the turbine section. In this part, we find a turbine mounted on the shaft we mentioned. Called the Compression Turbine, it’ll use some of the hot gases to power the compressor -the cycle is completed. Another turbine, on his own shaft, is located here. This is the Free Turbine, and that’s what makes your rotor turn.
Turbine Engine has a couple of major parameters: the RPM and the EGT – Exhaust Gas Temperature. The more fuel you send in your combustion chamber, the more power you create. The Exhaust Gas Temperature and the Pressure will rise. In turn, your compressor and free turbines gets more power.
But you just can’t indefinitely ask for more power. The engine cannot sustain hell for long. Heat and wear generated from friction will damage the components, and the engine lifetime will badly suffer from it. At some point, they are fire hazard.
- 400 to 610 ºC Continuous.
- 610º to 625ºC Take off power. Maximum 30 seconds
- 625 to 675 Maximum 10 seconds -only for starting or acceleration
- 675 to 760 Maximum 5 seconds -only for starting or acceleration
- 760ºC Maximum. -only when you want to fry your crew
- Engine RPM N1>101.5%
Reaching and exceeding these temperatures are not guarantee of an immediate failure. However, they will wear and damage your engine, severely reducing their performance. Even if you return to normal operating condition, the damage your turbine sustained will be sensible in the maximum power output. A worn out turbine may look all right while you are cruising at 100 knots – but eventually, when you will need more power to hover land or takeoff, that worn engine will not have enough punch to do the job.
Getting out of the documents
Belsimtek explained us what the end story is for the virtual UH-1. Modelling an engine is hard – even if you have documentation. accurately modeling an undocumented failure…. It’s a bit of a challenge !
Operating manuals, diagrams, warnings, tests…. All those sources usually indicate the limit of your engine. They don’t specifically (and technically) tell you what happens next. And that is where a developer can struggle, when he is looking for accuracy.
Back into DCS. 4 years after the Huey entered our virtual world, they are still many UH-1 flying around. The popularity of the virtual helicopter has reached the same level than the real one. Even after all the time, their pilots are still going in for a good surprise.
Engine fire will be added in next DCS Patch.
We spoke to Belsimtek about the issue and the main problem they were facing was the lack of documentation about engine fire. It is not like they are many testimonies of UH1 pilots crossing the suicide temperature and flying back to tell about it. Likewise, specifications are usually a bit lower than what the real deal can handle, because of safety margin. So Belsimtek main issue was to get enough data to achieve realism.
Upcoming patch will contain the updated engine management. Along with the engine fire, a small issue was found with the ground effect altitude.
Now, Huey pilots will have to take care of their beast!
Wait, wait… and the Mi-8?
We also talked about the Mi-8. Belsimtek explained us that this helicopter has safety that will prevent him to burn that easily. Safety margins are quite large. Over revving the engine will certainly damage it, but not up to the point it will stop and burn. If one of the engine fails, the other can sustain the flight in take/off power up to 1 hour (remember ? 30 seconds for the Huey) – Yet the engine will get so badly worn that it will get trashed at arrival.
Doesn’t prevent your engine from taking fire after a bad weapon hit…
Thank you Belsimtek for providing us that insight into development things !
Did you know ? the Lycoming T-53 engine development team was lead by Anselm Franz, the developer of the Me-262 engine ! IL2 1946 pilots will immediately recall that turbine engine, which was prone to catch fire anytime, for any reason !