BK117
The problem in the turn sounds a lot like the Puma yaw/roll divergence. Happens if too much in turn pedal is applied. The disc's flapback becomes offset - flapping the disc into the turn. Impossible to get out with cyclic, but top pedal works every time.
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These are the kind of things that scare me about helicopters, when they do things that they normally wouldn't do. To think that it was one of my dreams to fly a BK just because of the manuverability.
While at Bell School I was shown a video of a BO105 that was doing some sort of aerobatic routine, it was painted in primer and white and N registration, anyway during one of the low level tight turns he just kept turning until he hit and the ground and exploded into a ball of fire.
While at Bell School I was shown a video of a BO105 that was doing some sort of aerobatic routine, it was painted in primer and white and N registration, anyway during one of the low level tight turns he just kept turning until he hit and the ground and exploded into a ball of fire.
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Helmet
Now that the terms of SPAS and Vne are mentioned in the same sentence it probably looks like a possible SPAS computer problem as it only works within the longitudinal cyclic axis.
And we all know the FLM requirement if your SPAS in inoperative.
At the risk of getting beaten
- have you posed the question to Eurocopter in Donauworth? I have done that in the past with surprisingly good feedback.
Merry Xmas to all
Now that the terms of SPAS and Vne are mentioned in the same sentence it probably looks like a possible SPAS computer problem as it only works within the longitudinal cyclic axis.
And we all know the FLM requirement if your SPAS in inoperative.
At the risk of getting beaten
- have you posed the question to Eurocopter in Donauworth? I have done that in the past with surprisingly good feedback.Merry Xmas to all
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Helmet Fire,
I have experienced the BK pitch up a couple of times and in different machines, One with a SAS system and the other with AP.
It tended to happen at 60% matched TQ in the cruise. Each time it happened there was some kind of turbulence about be it from CU or TS/CB activity in the area.
It only managed to hit the stops on one occasion, a bit un-nerving, but it came good with full forward cyclic and no collective movement. Recovery was not too dramatic, it came back fairly gently after about 35-40 degree pitch up and only lasted about 5 seconds all up. I think the trick is to feel it and catch it early as I have had it happen to various degrees on other occasions and with quick reaction on forward cyclic it knocks it on the head and it doesn't get out of control.
Someone mentioned the tendency for the BK to tuck into a RT turn at high bank angles below 40KT. I don't have a RFM with me for the BK at the moment but I am pretty sure the BK117-B2 manual has a warning note about this somewhere... You might be able to find it in your RFM??
Welcome to the BK pitch up club!!!
I have experienced the BK pitch up a couple of times and in different machines, One with a SAS system and the other with AP.
It tended to happen at 60% matched TQ in the cruise. Each time it happened there was some kind of turbulence about be it from CU or TS/CB activity in the area.
It only managed to hit the stops on one occasion, a bit un-nerving, but it came good with full forward cyclic and no collective movement. Recovery was not too dramatic, it came back fairly gently after about 35-40 degree pitch up and only lasted about 5 seconds all up. I think the trick is to feel it and catch it early as I have had it happen to various degrees on other occasions and with quick reaction on forward cyclic it knocks it on the head and it doesn't get out of control.
Someone mentioned the tendency for the BK to tuck into a RT turn at high bank angles below 40KT. I don't have a RFM with me for the BK at the moment but I am pretty sure the BK117-B2 manual has a warning note about this somewhere... You might be able to find it in your RFM??
Welcome to the BK pitch up club!!!
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Bk117 ECS
When flying with ECS on the #1 eng's TOT is about 30-40 degrees hotter than the #2.
( I have flown 4 different machines always the same )
My question is : Do I match the TQ or match the engines, does it matter ?
I have asked numerous people and searched the flight manual and I am still no closer to an answer.
Thanks in advance.
( I have flown 4 different machines always the same )
My question is : Do I match the TQ or match the engines, does it matter ?
I have asked numerous people and searched the flight manual and I am still no closer to an answer.
Thanks in advance.
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Well unless your machine has very well behaved "flow fence actuators" your always gunna be trimming the engines anyway ....
The answer depends on how much ITT or Tq you have before you hit your limits..... I would fly matched Tqs in cruise and then watch how close you get to your limits... adjust as desired.
Just rem to turn OFF the ECS on approach !!!
The answer depends on how much ITT or Tq you have before you hit your limits..... I would fly matched Tqs in cruise and then watch how close you get to your limits... adjust as desired.
Just rem to turn OFF the ECS on approach !!!
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Blade Root,
Normal convention is to remain with the torques. No doubt you have found that the BK's normally torque out well before temping out, so we monitor torques as the primary limit.
If your interested, the temperature difference is due to one of the ECS valves sticking. There is one on each donk feeding bleed air into the aircon. If one is not opening fully then the other pumps more bleed air thereby getting hotter.
Otherwise a great aircon and a top machine.
Cheers
Normal convention is to remain with the torques. No doubt you have found that the BK's normally torque out well before temping out, so we monitor torques as the primary limit.
If your interested, the temperature difference is due to one of the ECS valves sticking. There is one on each donk feeding bleed air into the aircon. If one is not opening fully then the other pumps more bleed air thereby getting hotter.
Otherwise a great aircon and a top machine.
Cheers
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BK117 models
I couldn't find a thread dedicated to the vomit comet, so here we begin.
I recall a breakdown being posted in a thread of the various BK models and the differences between them. I can't find it, so unless somebody's kind enough to post a link, I'd like to know;
What the differences were
Which serial numbers delineated the change
Did Kawasaki serial numbers correspond with MBB/Eurocopter ones, or are they in separate sequences?
Did the EC145 continue the sequence or start a whole new one?
I recall a breakdown being posted in a thread of the various BK models and the differences between them. I can't find it, so unless somebody's kind enough to post a link, I'd like to know;
What the differences were
Which serial numbers delineated the change
Did Kawasaki serial numbers correspond with MBB/Eurocopter ones, or are they in separate sequences?
Did the EC145 continue the sequence or start a whole new one?
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Here is a general listing of the production/serial number ranges of the various BK117 models produced by MBB/Eurcocopter and Kawasaki over the years:
http://www.helionline.de/bk117.htm
Unfortunately, the links on the website don't work anymore, but nevertheless, it will give you an idea.
The BK117 A1, A3 and A4 models came equipped with Lycoming LTS-101-650 turbines, the B1 and B2 models with Lycoming LTS-101-750 turbines, and the C1 and C2 models with Turbomeca Arriel 1Es.
The B2 and C1 models both have slightly beefier (wide chord) tailrotor blades, which boost the MTOW compared to the A-3, A-4 and B-1 models (see Eurocopter BK117 Upgrade.pdf).
The EC145, or if you will BK117 C2, essentially is a stretched and beefed up version of the BK117 C1, with a higher MTOW, revised tapered main rotor blades and an EC-135 nose and cockpit wedged onto the front of it. Eurocopter markets it worldwide as the EC145, whilst Kawasaki has the rights to market the aircraft in the Australasia region as the BK117 C2.
Incidentally, if you check the serial number/production plates of all the EC145s produced by Eurocopter in Germany, the aircraft still is certified as a BK117 C2 (despite it being called the EC145). By certifying the aircraft as a further development of the original BK117, the development costs were kept to a bare minimum and Eurocopter avoided having to go through all sorts of certfication testing associated with a brand new aircraft. Same idea as the EC130 B4 being a further development of the AS350 B3.
More information is also available under Airliners.net.
http://www.helionline.de/bk117.htm
Unfortunately, the links on the website don't work anymore, but nevertheless, it will give you an idea.
The BK117 A1, A3 and A4 models came equipped with Lycoming LTS-101-650 turbines, the B1 and B2 models with Lycoming LTS-101-750 turbines, and the C1 and C2 models with Turbomeca Arriel 1Es.
The B2 and C1 models both have slightly beefier (wide chord) tailrotor blades, which boost the MTOW compared to the A-3, A-4 and B-1 models (see Eurocopter BK117 Upgrade.pdf).
The EC145, or if you will BK117 C2, essentially is a stretched and beefed up version of the BK117 C1, with a higher MTOW, revised tapered main rotor blades and an EC-135 nose and cockpit wedged onto the front of it. Eurocopter markets it worldwide as the EC145, whilst Kawasaki has the rights to market the aircraft in the Australasia region as the BK117 C2.
Incidentally, if you check the serial number/production plates of all the EC145s produced by Eurocopter in Germany, the aircraft still is certified as a BK117 C2 (despite it being called the EC145). By certifying the aircraft as a further development of the original BK117, the development costs were kept to a bare minimum and Eurocopter avoided having to go through all sorts of certfication testing associated with a brand new aircraft. Same idea as the EC130 B4 being a further development of the AS350 B3.
More information is also available under Airliners.net.
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Here is a link to an uncommanded pitch up event to a BK 117 B2 on the ATSB website.
http://www.atsb.gov.au/publications/...200506614.aspx
http://www.atsb.gov.au/publications/...200506614.aspx
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BK 117 Sim
Elmur
No such animal but ready to be proven otherwise. MBB had a BO105 sim but don't know if it still exists.
In Aus, you have to do it in the aircraft itself. What sort of flight crew training are you looking at? PM me if you would like to discuss.
No such animal but ready to be proven otherwise. MBB had a BO105 sim but don't know if it still exists.
In Aus, you have to do it in the aircraft itself. What sort of flight crew training are you looking at? PM me if you would like to discuss.
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Potential Client of mine has an interest in a BK117C-1 but I hear they are in short supply? Any ideas on prices for a pre-owned EASA machine? Not my usual market see...! Cheers for any info.
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@ ELMUR ADAC Luftrettung (Germany) is planning to buy 2 fullmotion flight-simulators. They are supposed to be running in spring 2008. One will be a EC145 simulator. sky2000
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In regards to the ECS turned on resulting in a higher temperature on one engine it is clear that only one of the ECS air valves is working correctly. These are of a design that wears and has poor sealing surfaces. We check them every 300 hours for correct sealing and have a test fitting which regulated air pressure is applied and the valve actuated to ensure correct function.
As for the pitch up, It is reasonably unique to BK117s.
When the BK117 is: High, heavy and apporaching VNE the design of the rotor system (rigid) and profile of the aircraft (long, large surface area belly) become factors in causing pitch ups.
To avoid this condition it is advised to fly at a a speed below the VNE markings for that altitude. We have had several cases in Africa where the autopilots engaged and a wind change or turbulence will cause a rapid pitch up which the autopilot can not rectify. The Autopilot was deisgned more for the BK117 at lower weights and the duplex pitch actuator does not have the authority to overcome such rapid pitch changes uninitiated by the pilot.
If the aircraft control rigging is carried out correctly and the aircraft flown IAW the VNE limitations the chance of pitch ups is greatly diminished! The maximum torque check for the collective overide spring to be reached is a good indicator to ensure the rotor system is not overpitched which exacerbates the pitch up problem. This requires correct flight control rigging and engine torque calibration.
As for the pitch up, It is reasonably unique to BK117s.
When the BK117 is: High, heavy and apporaching VNE the design of the rotor system (rigid) and profile of the aircraft (long, large surface area belly) become factors in causing pitch ups.
To avoid this condition it is advised to fly at a a speed below the VNE markings for that altitude. We have had several cases in Africa where the autopilots engaged and a wind change or turbulence will cause a rapid pitch up which the autopilot can not rectify. The Autopilot was deisgned more for the BK117 at lower weights and the duplex pitch actuator does not have the authority to overcome such rapid pitch changes uninitiated by the pilot.
If the aircraft control rigging is carried out correctly and the aircraft flown IAW the VNE limitations the chance of pitch ups is greatly diminished! The maximum torque check for the collective overide spring to be reached is a good indicator to ensure the rotor system is not overpitched which exacerbates the pitch up problem. This requires correct flight control rigging and engine torque calibration.
Chief Bottle Washer
Airwork NZ have a significant LTS101 upgrade approved:
Honeywell Announces LTS101 Upgrade Flight Tests Complete
Honeywell (NYSE: HON) announced today that flight testing of the LTS101 engine upgrade from Airwork New Zealand for the Eurocopter BK117 has been completed.
All flight testing has been completed and paperwork has been submitted to the Civil Aviation Authority (CAA) of New Zealand. A Supplemental Type Certificate is anticipated shortly. This will be followed shortly afterwards by European Aviation Safety Agency (EASA) and the United States Federal Aviation Administration (FAA) certifications.
The LTS101 upgrade, which updates the engines to the LTS101-850B-2, delivers 15 percent more take off power and 18 percent more power for hot day operations.
“The LTS101-850B-2 engine is a drop-in replacement with no external changes,” said Paul Vidano, vice president, Militaries and Operators, Honeywell Aerospace. “Operators can upgrade their engines during normal scheduled inspection intervals or through direct purchase and core credit.”
“Flight testing revealed the Honeywell-powered BK117 exceeds the BK117 C-1 performance,” said Kevin Johnson, group CEO of Airwork. “The LTS101 upgrade will provide significant benefits for BK117 operators.”
“The LTS101 upgrade more than doubles gas producer disk life to 15,000 cycles by incorporating the cooled gas producer turbine assembly, reducing direct operating costs by extending the life of the gas producer turbine,” said Doug Kult, sales director, Commercial Helicopters, Honeywell Aerospace. “Operators get additional performance without sacrificing fuel economy.”
One Engine Inoperative (OEI) power increases by 14 percent, providing a 12 percent increase in maximum OEI hover weight, which increases safety during single engine operations. Hot day takeoff power increases by 18 percent, resulting in a 13 percent increase in maximum takeoff gross weight. A 20 percent hot day continuous power increase results in a 25 percent reduction in the time to climb from sea level to 10,000 feet, a three-minute savings.
The LTS101 engine family has accumulated more than 10 million flight hours of operation. Honeywell has continuously invested in engine improvements through the infusion of new technologies and upgrades. As a result, the engine family has demonstrated a four-fold improvement in reliability since 1996, and unscheduled removals and warranty claims have been driven to the lowest values in the history of the engine.
Honeywell offers a full range of helicopter equipment, from aircraft engines, auxiliary power units and other mechanical systems to the Zing™ Health Usage Monitoring Systems (HUMS). Honeywell's safety systems for helicopters address the challenges of traffic, terrain and weather, helping to ensure safe flight and guard against Controlled Flight Into Terrain (CFIT), weather related hazards, and collisions with obstacles and other aircraft.
Honeywell (NYSE: HON) announced today that flight testing of the LTS101 engine upgrade from Airwork New Zealand for the Eurocopter BK117 has been completed.
All flight testing has been completed and paperwork has been submitted to the Civil Aviation Authority (CAA) of New Zealand. A Supplemental Type Certificate is anticipated shortly. This will be followed shortly afterwards by European Aviation Safety Agency (EASA) and the United States Federal Aviation Administration (FAA) certifications.
The LTS101 upgrade, which updates the engines to the LTS101-850B-2, delivers 15 percent more take off power and 18 percent more power for hot day operations.
“The LTS101-850B-2 engine is a drop-in replacement with no external changes,” said Paul Vidano, vice president, Militaries and Operators, Honeywell Aerospace. “Operators can upgrade their engines during normal scheduled inspection intervals or through direct purchase and core credit.”
“Flight testing revealed the Honeywell-powered BK117 exceeds the BK117 C-1 performance,” said Kevin Johnson, group CEO of Airwork. “The LTS101 upgrade will provide significant benefits for BK117 operators.”
“The LTS101 upgrade more than doubles gas producer disk life to 15,000 cycles by incorporating the cooled gas producer turbine assembly, reducing direct operating costs by extending the life of the gas producer turbine,” said Doug Kult, sales director, Commercial Helicopters, Honeywell Aerospace. “Operators get additional performance without sacrificing fuel economy.”
One Engine Inoperative (OEI) power increases by 14 percent, providing a 12 percent increase in maximum OEI hover weight, which increases safety during single engine operations. Hot day takeoff power increases by 18 percent, resulting in a 13 percent increase in maximum takeoff gross weight. A 20 percent hot day continuous power increase results in a 25 percent reduction in the time to climb from sea level to 10,000 feet, a three-minute savings.
The LTS101 engine family has accumulated more than 10 million flight hours of operation. Honeywell has continuously invested in engine improvements through the infusion of new technologies and upgrades. As a result, the engine family has demonstrated a four-fold improvement in reliability since 1996, and unscheduled removals and warranty claims have been driven to the lowest values in the history of the engine.
Honeywell offers a full range of helicopter equipment, from aircraft engines, auxiliary power units and other mechanical systems to the Zing™ Health Usage Monitoring Systems (HUMS). Honeywell's safety systems for helicopters address the challenges of traffic, terrain and weather, helping to ensure safe flight and guard against Controlled Flight Into Terrain (CFIT), weather related hazards, and collisions with obstacles and other aircraft.
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As a matter of interest, does anybody here know if the yellow attachments on the underside of the belly of this BK-117 are auxiliary fuel tanks (combined with a set of flight-steps of sorts)? Google so far is drawing one blank after another...