BK117

[Scattercat]

Has anyone else had un-commanded pitch-up occurences in BK117's(around 20 degrees)in moderate turbulence ? This has happend twice to me now at night in IMC & it feels rather uncomfortable! The CSAS has been thoughly checked out and cleared.

[rotorcaptain]

High DA in moderate turbulence coming out of Yosemite National Park with a patient on board. I attributed my pitch up more to Retreating Blade Stall than a CSAS problem.

[This message has been edited by rotorcaptain (edited 25 May 2000).]

[before landing check list]

I agree, was there a slight left roll at the moment of pitchup?

------------------
carpe diem

[Scattercat]

Not that I recall. I wondered at the time if it was caused by airflow disruption over the horizontal stab'. ie: An initial turb' induced pitch-up causing the airflow to "spill" off the horiz' stab which then exacerpated the situation?

[Magumba]

Could your csas have gotten kicked off momentarially? I find nose =-20 degrees is normal flight in a BK in turbulance. Seems you are always fighting to keep the nose on the horizon even in light turbulance. Of course I could have had the problem and not known. It's also possible the gust was too much for the csas to handle. It's not a very good system compared to the single pilot IFR SPZ 700.
Give me the S-76 any day.

[Scattercat]

No, I would have gotten CSAC caution lights up. The whole event took about 5-10 sec's. ie: long enough to see any lights.
By the way I agree, give me back the S76!!

[whatsarunway]

Does anyone know what the bk117 is like in the ems role , we are starting a small ems operation and are hearing lots of differing reports on the bolkow is there anything better or any comments would be handy

-------thanks--------

[Marco]

Devon & Cornwall Constabulary Air Support Unit operate a BK117. Albeit mainly in the police role they do a limited amount of EMS when Air Ambulances are not available. if you don't have their details they're all in Shephard's 'Police Aviation Handbook'. Any more difficulty e-mail me.

[rotorcaptain]

I fly a BK117 in California in an EMS role. It is excellent and very popular in the states. The B2 model is very strong and performs well in high DA situations. It's great for night operations since the cabin is separate from the cockpit, no bother from the patient or the interior lights. It's a stable platform for IFR but I understand that it doesn't have the range to be very effective. The medical crews like it as well. Two patients or one. The interior is key, take your time in designing it.

Let me know if you need any more info.

[helidrvr]

the BK is probably the single most popular EMS ship in the USA. Suggest you contact Keystone Helicopters. They operate a fleet of BK's as well as an assortment of other ships (S76, A109 etc.) and are one of the premier EMS completion centers in the US as well.
http://www.keystone-helicopter.com/

[whatsarunway]

many thanks to all im going over to mcalpile in the uk on the 28th to findout more is there anything to look for in a second hamd one???
thanks again

[Capt.Essential]

I Like the BK117. For Many of the tasks mentioned. Has anyone used them for fire-fighting?

[whatsarunway]

ive heard irish helicopters used a 212 and a bk 107 for fire fighting but never a 117

[This message has been edited by whatsarunway (edited 17 June 2000).]

[Magumba]

Whatsarunway,
I've flown the BK and BO in EMS, if I had to make a choice I'd take the BK. But if there is an S-76 available I'd jump in that first.
With regards to the BK-117, try to avoid the "A" series helicopters, a bit weak. The B-1 or even better the B-2 have more umph on takeoff. Some of the A's do not have yaw sass I understand, you want to be sure you get a machine with yaw sass. (Yaw sass was added due to the number of med crew getting air sick) Even with yaw sass I find the patient, and often the med crew, get sick in the BK-117. It's a much more sharp edged ride in turblence then any other helicopter except the BO-105. In my experience 10 gusting to 15 feels like 20 gusting to 30 in most other helicopters.
In spite of the room in the back the patients side rubs the side wall on loading so we have had problems with a patient with a broken right arm or leg "fitting" comfortably. Lots of loud comlaint.
I'm also not crazy about the hydraulic system in the BK, same type as the BO. The no 1 system is carring all the loads all the time, then if it fails you have to rely on an automatic switch over to the no 2 system to keep the controls working. There have been a few situations during the switch over where the collective slams down. Good idea when you do the pre-takeoff hydraulic check to leave the collective up a little during the switch over check to see if it drops. An engine overspeed control system has recently been added to the BK too. I have heard of a few situations of it causing a loss of power due to a false sense of an overspeed. Also the overspeed test switches are not "locked out" at 100% N2 so if you move one to test in flight, by mistake, you can have a momentary loss of power, even a shut down in some cases.
Some one else mentioned fuel. Make sure you get the small aux tank, the early A's did not have it. Gives you 180 US gal of fuel. About 2+15 to burn out at 60% torque in the A or B-1 @ 120 kts. Not great for IFR IMO.
Hope this helps you in deciding whether to buy a BK or not. For the cost of a new one you can have a great used 76 which is a much more capable helicopter.
Fly safe.

[Love Monkey]

The BK117 variants, whilst being superb all-round helicopters have a couple of very nasty vices which can/have caused accidents or messed flightsuits (to say the least). In particular, the severe pitch-up at high DA/AUW/IAS combinations, and the inability to recover from a steep right roll at sub 40kt airspeeds. Can anyone shed some light on the causes of these and more importantly, are there any plans/mods to have these problems alleviated in later models (EC145)?

Cheers,

The Monkey.

[Hingeless Rotor]

Unfortunately I have encountered both the problems you describe, but cannot shed any technical light on the causes, less to say that they are aerodynamic. The pitch up is a bit disconcerting, especially at night, as it can be as high as 20/25 degrees. I had put it down to the SPAS applying a correction to the stick position as a result of the applied cyclic when correcting the pitch up, but have since come to the conclusion that it is an instability problem. When it happens you get the distinct feeling that you have no pitch control for a couple of seconds.

If your interested you can also get locked into a tight left bank in the BK. Once again I found myself in this position doing a low level exercise and thought I was about to literally slide slip into the ground from about 20 feet with full opposite (right) stick displacement. Thankfully it held its height (only barely) as it decelerated in the uncontrolled turn, from about 80 knots to 5 knots in less than 3 seconds. Scared the crap out of me. I have since found that applying a small amount of opposite pedal and forward cyclic will bring the old girl out of any high angle of bank, albeit with low G’s.

Your right, it’s a pretty well know problem and one I think we just have to deal with from inside the cockpit as it is probably inherent in high performance helicopters.

Give my best to your monkey, ;)

Cheers

[Love Monkey]

Didn't know it could happen to the right. The pitch up is (I am led to believe) caused when there is not enough fwd stick remaining to counter flapback at high blade pitch angles caused at high DA/AUW/IAS combinations, even with a servicable SPAS. Can anyone can verify this?? Lowering collective fixes the condition, but not after you lose 40-50 knots and 10-20 years off your life (double this at night). Does this happen on the EC145?:sad:

[John Eacott]

"Taught" about this quirk during endorsement training, but never been able to reproduce it operationally. I was led to believe that it was affected by the rigging, and substantially reduced/eliminated with the B2 upgrade, which revised the rigging and pitch horns. As such, I would expect that the 145 should limit the problem, but that's only a guess.

I have had instances of pitch "running away" nose up at altitude, when IAS has got on the high side, which has either needed gobs full of forward cyclic or a pedal turn/roll to reduce. Talking about DA>6000ft, though. It can be a bit twitchy up around 9-10,000 ft, but the collective is usually around the pitch limit there, anyway, so most flying is with the trim rather than brute force ;)

(Just a late thought, but reducing collective is sometimes a solution to the pitching up problem, but not always. But it helps at high DA)

[SASless]

During Factory training....and demo of the low altitude, steep bank, roll coupling....no more lateral cyclic situation.....advice was to use as much opposite pedal as required to regain control. Main concern is regaining control and use of full pedal is acceptable....the little ****** is "rigid rotor" (my definition....not Lu's) thus it is tolerant of "G's" or the lack of. At least it is far more tolerant of them in the air than when making contact with the ground at a high rate of knots!

Right turns are the problem...first I have heard of a left turn presenting a problem.

[PPRUNE FAN#1]

Hingless Rotor wrote:I had put it down to the SPAS applying a correction to the stick position as a result of the applied cyclic when correcting the pitch up, but have since come to the conclusion that it is an instability problem. When it happens you get the distinct feeling that you have no pitch control for a couple of seconds.Haven't flown the BK, but the MBB BO105 has a very similar rotor with similar characteristics. One day, up high and scooting right along, I caught a little updraft (I guess) and the nose pitched up. And up, and up. I kept feeding forward cyclic in, with no response, thinking, "This is a bit odd, eh what?" Finally I did lower the collective and returned to controlled flight. I came to the conclusion that my little BO-peep did not like high-altitude flight all that much.

[Love Monkey]

The roll to the right is a similar problem to the pitch up. The control rigging doesn't have enough play to counter inflow roll in that condition (right bank / low IAS). Seems like a fairly significant design flaw for a popular production helicopter. Nothing about it in the flight manual either. Still love the machine though, brilliant little workhorse. Any mods known to fix it? Many military users out there?

[helmet fire]

I have not yet experienced either of these vices operationally, however, i have heard the pitch up discussed over many beers, and the remedy that seemed most popular was to lower the collective. Several whom claim to have experienced the pitch up swear it works a treat.

As for the lasck of cyclic, I too thought it was a right turn. I saw it demonstrated on my endorsement (as I guess ALL BK drivers should have). I believe it is to do with rigging - and in particular, length of the pitch change rods. part of the B2 upgrade was a lengthening of the rods to compensate for this problem, and it does a good job of reducing it's impact - but it doesn't eliminate it altogether. Hopefully you will not experience it in a B2 operationally as it takes some agressive handling to get it into the condition.

Love Monkey (BTW, love the name!! :ok: ) you asked the question at the top, and then you answered yourself down here! How did you come across your answer?

And your call that it "seems like a significant flaw" is a big one. I reckon that they have sorted the roll issue out with the B2, and the pitch up seems to be relatively easily compensted for.

[Hingeless Rotor]

I must admit that I too was told the roll issue was normally to the right, but I can’t think of any other reason to explain why the machine reacted the way it did in the left bank.

My understanding of the situation was limited to the ‘results’ as apposed to the ‘cause’.

Out of a vested interest - Is there evidence that suggests it couldn’t happen to the left? And wouldn’t the ‘nose high’ situation, stated above as possibly being the same thing, suggest it could happen at any attitude?

[helimatt]

Severe nose pitch up at high IAS/AUW/DA and corrected by lowering collective;...... Please correct me if this is a really ignorant and simple answer to a more complicated problem, but aren't these clasic retreating blade stall symptoms?

[splitpin]

I have seen the pitch-up on an almost regular basis when above about 10,000 DA and at high AUW and pushing the machine along at close to VNE for the conditions, but never seen it at low DA, AUW, or speeds.

I have always assumed that the pitch up was being caused by retreating blade stall. Lowering the collective certainly helps correct the pitch up which is consistant with the recovery technique for retreating blade stall as well.

[C4]

BO-105 has a control box (Cyclic range of movement) that is rectangular in shape. The rectangle runs longitudinally and is offset to the right, so there is less cyclic movement to the left than right.
This equates to: low speed steepish turn to the right, move cyclic left to roll out and hit the cyclic left stop... There is enough cyclic to reverse the turn, but takes time.. With low altitude.. time equals height and a very spectacular PRANG....

Rule # 1 in BO-105.. Low level turns are always to the LEFT...

Cannot recall if BK has the same problem.. (Don't thinks so mind you)

[[email protected]]

I believe this is a similar handling quirk to that of the Lynx and is common to many helis with 'rigid' ie high hinge offset rotor heads.

It would take the venerable Nick Lappos or demi-god Shawn Coyle to explain it correctly but in normal flight conditions the rigging, advance angle, pitch horn position et al can be arranged to match the phase lag (not usually 90 degrees with high hinge offset rotors). This means that where you move the cyclic, the rotor will obediently follow.

But when you start to manoeuvre the heli, especially in a tight turn the dynamics of the rotor response produce a pitch-roll coupling because the phase lag is no longer perfectly matched to the rigging - so when you pull back on the cyclic the rotor pitches up but also rolls right forcing you to oppose the motion with left cyclic. Now you are in a right turn with left cyclic applied, meaning your control margins for rolling out have been seriously reduced.

This phenomenon is very noticeable on the Lynx in high AoB turns, quickstops, wingovers and pitching display manoeuvres (back flip, loop etc that are flown AFCS out)

[SASless]

For you BO and BK drivers....ever try to fly the aircraft using collective movements to control roll? In cruise flight....roll attitude can be controlled by use of the collective if you are patient and catch on to which way the aircraft reacts to those collective movements. That will demonstrate much of what Crab is saying about cyclic/collective roll coupling.

[PPRUNE FAN#1]

SASless:For you BO and BK drivers....ever try to fly the aircraft using collective movements to control roll? In cruise flight....roll attitude can be controlled by use of the collective if you are patient and catch on to which way the aircraft reacts to those collective movements. That will demonstrate much of what Crab is saying about cyclic/collective roll coupling."...In cruise flight." Heh. Not in a Boelkow, old boy. Cruise flight in a 105 (around 120 knots) is denoted by a healthy 8 - 10 degree nose-down pitch attitude. At such an attitude, leaving the cyclic unattended for any length of time results in the a/c trying to turn itself inverted.......regardless of what you do with that lever next to the seat. I've flown a lot of different 105's (including some that their regular pilots proclaimed to be "very stable"), and NONE of them would stand more than about 9 or 10 seconds of hand-off-the-cyclic before departing S/L flight no matter how well-trimmed I could get it.

At 60-70 knots however, it is fun to fly the BO by using the collective alone. At those speeds it is "relatively" stable, although I laugh at the very thought of using the words "stable" and "Boelkow" in the same sentence.

I had an amusing conversation with a Boelkow pilot once. It enlightened me as to how fiercely loyal and unobjective pilots can be about their aircraft. This guy was going on and on about how wonderfully stable the 105 was. I was chuckling to myself and shaking my head. When he finally stopped to take a breath, I managed to interject my little discovery about how they'll start to go upside down in an average of seven seconds if you take your hands off the cyclic. He immediately replied, "Yeah, they do that."

This man obviously had no earthly idea what constituted "stability" as it applies to helicopter flight.

His "solution" was novel. "What power-setting do you fly at?" he asked. I said, "120 knots, and whatever it takes to get me there." He then said, "Well that's your problem! You're cruising too fast. Slow it down to 100 knots and it's VERY stable."

He was dead serious too, as far as I could tell. I think he was trying to get me to believe that when he flew the 105, he drove around at 100 knots watching everything from Astars to 407's blow by him. Sorry chaps, but I've spent my life in 70 knot Bell 47's, 90 knot 206B's and 104 knot 206L's. I'm not about to reign in a ship that can "scoot" at 120. And I don't think most other 105 pilots do either.

And for the record, the 105 isn't all that much more stable at 100 knots than 120. It's better......but that's not saying much.

[[email protected]]

Sasless, as you say this use of collective demonstrates the pitch roll coupling common to many 'rigid' rotors because the raising of the lever causes the disc to flapback (instability with AoA and true of all helicopters). The resultant roll or lack of it will tell you if the phase lag is 90 degrees or not (as mentioned earlier it reduces with effective hinge offset).

[2bart]

Anyone know where I can find out how many BK 117's have been produced and how many were C1's.
I hear the last one is in production and sold to Italy.
Are there any operating in the UK?

[zalt]

One operated by Devon and Cornwall police.

I remember hearing some story that the last C1s were to be assembled in Italy to clear space for EC145.

[PANews]

Try www.Rotorhub.com it has links to production lists.

They are not 100% accurate but they will give you good idea.

I will now go and wash my mouth out with salt for promoting that that is not mine!

[Anton van Dellen]

Staffs and West Mercia Police run a joint one out of Ha'Penny Green/Wolves Business Airport. Lovely machine and very courteous crew/pilots.:ok:

[zalt]

I thought Central Counties (Staffs and West Mercia) had an EC135 now?

[Dynamic Component]

Don't know much about BKs so I'm after someone that can give me more info about the models, usable payload, range, external load capacity, pax numbers etc.
:confused:

There must be many a pilot out there that can help me.:}

Which is the best(not necessarily newest) BK model out there(excluding the C2/EC145)

Thanx in advance for your help:E

[spinningwings]

Best model would have to be tha Bk117B2 with all ADs and SBs complied with... including the installation of the C mod tailrotor. ...

...If you go ahead and get one(?) try to get (buy, beg ,borrow or steal) the tooling to set up the tailrotor hub (fork) bearings.

Enjoy.......

[trackdirect]

BK117 A4 modified to B2
LTS 101-750B1 engines (750 HP)
Payload max gross 3350kg up from 3200kg
Max gross with external load 3500kg (up by 300kg)
Improved CAT A performance up to 280kg higher payload

Upgrade kit for A4 to B2 includes
Uprated engines (750 hp)
new T/R blades (improved design)
Increased pitch range of MR blades
Uprated OEI Main gearbox limit (2.5 min limit up from 100% to 125%)
New engine instruments (different limit ranges)

To upgrade from A1 or A3 to B1 the A/C must first be upgraded to A4 model

I believe the A1 and A3 had the 650 HP LTS these had quite a few problems and were often removed for inspection every service. Not a problem now with the 750 it has new GP Turbine Disc (single crystal) stopped cracking problem.
You may find that some A4s have been upgraded with the 750hp engine but have not been upgraded to a B2 because the kit can be quite expensive... I have heard that the torque gauge costs at least 20k US.

There have not been many major airframe mods throughout the range mainly engine mods to upgrade.
So the best bet may be to purchase an A4 and upgrade to B2 for a pretty good performer.

As for PAX you can have 8 in the back and 2 crew for a full load or may other variations of seating as required.

Max hook load is 1500kg but I think you would be lucky to lift about 1100Kg on average.

[Dynamic Component]

Anyone know what the fuel consumption and DOC are :confused:
And if you know of one thats for sale, please PM me.:ok:
:E

[John Eacott]

TD,

Picking at nits, but the max hook allowable on the 117B is 1300kg, and the upgraded Tq is an option, not a standard on the B2. Fairly expensive, as you say, requiring replacement Tq gauge & upgraded transducers (4 off), plus rescheduling of the FCU (IIRC, I'll have to check later). Similarly, the tail rotor blades are off the 117C model, and not a standard mod for -B2 upgrade. Really nice to have, though, and make a stunning difference to the aircraft, especially heavy and/or high altitude. With the standard tail rotor blades, cramp in the left calf was almost commonplace with all that left pedal needed, but I can only think of one or two occassions that the T/R has approached full left since we upgraded to the -C tail rotor.

Regardless of all the times that various Authorities tell us to only buy from manufacturers or OEI suppiers, a cautionary tale. When we fitted the -C TRB's, we also had a tail rotor assembly, complete from Eurocopter. On the first run, the pedals required 20-30lb force to hold neutral, and Eurocopter's response was along the lines of "get used to it, not our fault, there's a 117 in NZ the same problem, pilots hate it".

After a lot of checking, it turned out the factory had assembled the tail rotor hub using Bo105 weight arms :mad: When the correct parts were supplied, all became sweetness and light :rolleyes:



DC,

Fuel consumption about 300lt/hr, or 240kg/hr. DOC, and known aircraft for sale, PM or e mail me ;)

[spinningwings]

....Have to agree with everything John has posted...especially about the adjustment of the T/R "Bobweights" which are used to set (adjust) pedel forces .....

Cheers John ... ;) :ok:

[StevieTerrier]

Does anyone know if the Kawasaki-built BK117 is certified in the UK? I remember that some Scottish fire service (Strathclyde?) had one as a demonstrator some years back, but that may have been a "pukka" German-built version.

If it is not certified now, will it be under EASA, maybe?

[ginganinja]

how do new to this site but i can tell you the only BK-117 in the UK is G-DCPA with devon and cornwall police a 1995-C model from eurocopter

[Hippolite]

The Kawasaki built version is not certified in the UK, Europe or the USA. If you want one, you have to get a Eurocopter (MBB) built version.

Likewise, the MBB Built ones are not certified in Asia or Australia (although may be able to be certified in Oz??)

Thie thing is, that on the used market, a Kawasaki version is only worth around half of an MBB version. They are not inferior per se but it is part of the original Joint Venture between MBB and Kawasaki that they would be certified in separate markets.

The ability to earn money with a Kawasaki is therefore limited to cretain regions where traditionally, rates are lower so the revenue is lower. The used market judges them as such and that is why they are cheaper.

Hope this helps

HH:cool:

[trackdirect]

Hippo,

I know of one MBB117 in Australia, Been here since new... 14 years.

Trackdirect

[helmet fire]

The MBB is certificated world wide, and can be sold world wide. The marketing arrangement with Kawasaki was that the kwakas are limited to SE Asian makets, including Australasia (Aust, PNG, NZ, Pacific Isl)

Child Flight operated the region's second BK117 (after the NSW police took theirs swimming) and it wa an MBB one.

[StevieTerrier]

Thanks for your replies gentlemen, most helpful.

[widgeon]

I beleive there was a Japanese Bk imported to canada. The seller bought a japanese aircraft and an old american airframe and transferred the low time dynamic components to the US airframe . Back in the good old days there were many tax incentives to buying a helicopter in Japan and may were bought as tax shelters .

[rollie rotors]

Shock Trauma Air Rescue headquartered in Calgary Ab, operates four Eurocopter BK117 helicopters manufactured in Germany and Japan.

STAR-2, STAR-3 and STAR-4 are BK117 B-2D models and STAR-1 is a BK117 A-1D model.

[PANews]

In recent weeks the MD900 has taken the brunt of the bad press on Kawasaki gearbox failures ... I understand that West Midlands Police are now on their third box failure this year ... but the MD is not the only type to use Kawasaki gearboxes, the BK117 among others uses them.

So what is the history of Kawasaki gearboxes in the BK ... good or bad? Robust or weak?

[noooby]

From a mechanics point of view..... Bulletproof. A company that I worked for looked after 15 BK117's (A4/B1/B2), and in the 3 years I was there, they never did any unscheduled maint on the MGB. I did the Mast Spacer inspections for the company, and that would have to be the weak point, especially if you do alot of heavy lifting work with your BK, just about guaranteed to be replacing the Mast Spacer during the inspection due to wear. Keep on top of corrosion and paint condition. That magnesium sure does fizz when salty air gets on it!! The quality of the gears inside is very good. After 5000 hours, they usually look like they are new. It is surprising that the MD900 series has problems with a Kawasaki gearbox. The BK MGB's are built very well, and just keep going and going. Did you know that Kawasaki also do the inputs for the AB139 MGB?

noooby

[spinwing]

.... I have to agree with "noooby" ..... Bk Xmsns "Absolutely Bulletproof" .... Fly with confidence!


:ok: :ok: :ok: :ok:

[PANews]

I was not aware of the AB139 connection, but as a newer programme its track record would be less of an indicator than the old BK117.

So there must be another cause. I am no expert on gearboxes let alone the differences [if any] between the BK and the MD MGB but that leads us towards asking questions about design differences relative to the interior of the 900 MGB. Are cogs just cogs or have they changed materials?

Another train of thought might explore the differences in the dynamic forces affecting the power train of the 117 and the 900.

You do not see 900s '...do a lot of heavy lifting work...' and yet the 117 is said to be pretty resiliant against such abuse.

Does anyone have any further ideas?

[SilsoeSid]

Does anyone have any further ideas? Yep, How about changing your record PA News!

[Graviman]

Hmmm, i would question the duty cycle that the gearbox was undergoing. I imagine that Police choppers will do a lot more agressive manouvreing that most choppers. This means the mast thrust bearings and tail rotor output bearings will be seeing more load. Worrying when you consider rotor component fatigue lifes.

I can't imagine the power input being a problem, unless the engine is normally derated but has been increased for Police usage. It is possible they are using oil, which while being in spec, is not as durable thus reducing bearing life.

Really, i would need to know more about the actual nature of the failures to do anything more than speculate.

Mart

[Giovanni Cento Nove]

Last time I looked the BK117 gearbox was made by ZF in Germany.

[PANews]

Giovanni Cento Nove I guess you are wrong.... bearing in mind that engineers who have worked on them have already posted. There may be a mix across the fleet, but the BK117C1 has a Kawasaki KHI KB03 anyway.

The choice of the BK as the core of this question was honed in on the box.

As for Silsoe Kids comment about about changing records perhaps he has a view on the subject.

Perhaps he has not asked why the K boxes are causing problems 'all of a sudden' when it now seems pretty clear that other boxes by the same manufacturer have displayed anything but weakness.

Do you NEVER ask questions?

How do you hope to get answers?

[SilsoeSid]

PANews,

The reason I came up with my 'kids comment'as you put it, is because it seems to me that all you tend to do is enter or start a thread dangling your little line and when someone comes on board to discuss the subject against what you believe to be the facts, you suddenly become the expert in the said subject.

If you don't know the answer to a question, fair enough. Allow others to educate you.

However, if you know the answers, please post them and stop inviting opinions that more than likely are going to get the famous PANews reply along the lines of your last post to Giovanni.

Yes I have bitten your line, but you'll have to struggle like fcuk to get me reeled in!

A little research found,

http://www.zf.com/zf_luft/defaultz.asp?id=113&lang=1

ZF make intermediate- and tail rotor gearboxes for the BK117

'Overhaul and repair of transmissions'

"For the following transmission we can offer you either major overhaul, repair or exchange transmissions:

main transmission BK117"


Giovanni, I believe you may have an apology incoming!
:ok:


PANews, this thread title and most comments do not directly mention Main Gearboxes. Although most of us know what you are on about, it doesn't follow that Giovanni knows about your bitching!

ATB,

SS


All those who enjoy PANews' little lines, may I suggest buying the 'Another Monty Python Record,' LP, and listen to the 'Pirannha Brothers' track which is at the end of side 1. It has what is called a 'locked groove'. This means it goes on ad infinitum, well at least til the next power cut anyway!

Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...Sorry squire I scratched your record....sorry squire I scratched your record...................................................... ...




edited because I want PA to apologise to Gio.!!!

[PANews]

No apology offered.

Giovanni you said categorically the BK117 gearbox was made by ZF in Germany. Not specifically correct, but it seems that some probably are - but that is not what was said in the post.

The Giovanni statement appears to have directly contradicted Noooby [allegedly a mechanic who had worked on the beast - who was backed up by Spinwing] who offered an opinion that the Kawasaki gearbox on the 117 was a good bit of gear.

Perhaps this argument may therefore be with Noooby and Spinwing in their apparent confirmation that the models of BK they were aware of were using Kawasaki.

It may be that some models of the BK have ZF boxes, but as far as the thread goes this is a Kawasaki box thread ['bad press on Kawasaki gearbox failures'].

I am aware that there are Kawasaki boxes on the BK117C1 and that I am not aware of any major MGB problem reports on that type but that was probably the sum total of my knowledge at the time I posted. Hence the question.

From Noooby and Spinswing I have had my question on the usual capabilities of Kawasaki gearboxes succinctly answered.

The insertion of any ZF mention is therefore effectively a red herring.

Finally Silsoe .... in which posting did you actually get around to twisting quoted words of 'Silsoe Kids comment' into the slightly emotive .... 'kids comment' - have you been taking something? That was just a typo for Silsoe Sid, you even changed the Capitalisation in support of what was a clear distortion of the written word.

[widgeon]

Someone must have the IPC , it gives the manfg code quite clearly.
Is it possible that Japanese BK's have Kwakasaki and German ZF's . If i recall correctly there was quite a bit involved in taking an Asian airframe and retrofitting it so it could be used in North America . One of the Bk's flying for STARS in ALberta started out as a Japanese aircraft .

[SilsoeSid]

PANews,

I see once again you are suddenly the expert on this matter. :rolleyes:

Quote: "Giovanni you said categorically the BK117 gearbox was made by ZF in Germany."

No, he said "Last time I looked the BK117 gearbox was made by ZF in Germany."
Last time he looked! Main, intermediate or TR ? You cannot assume he knows you are talking about MRGs
ZF make intermediate and tail rotor gearboxes and overhaul MGBs for the 117.

Quote: "It may be that some models of the BK have ZF boxes, but as far as the thread goes this is a Kawasaki box thread ['bad press on Kawasaki gearbox failures']".
Is that why it is titled " BK117 gearboxes"?
Gio doesn't know you have a thing for MRGs, just that you tell him he is wrong, when he is correct in what he says.

Quote: "in which posting did you actually get around to twisting quoted words of 'Silsoe Kids comment' into the slightly emotive .... 'kids comment'"

As in the words, kids and comment being next to each other in the same sentence with no punctuation between them!

You may call ZF a red herring if you wish, because it suits your argument, but I would suggest you cease telling others they are wrong when you haven't seen what they may have.

ATB,
SS

[spinwing]

G'day Gents ....

Right ... the Bk117 main transmission is manufactured by Kawasaki and was jointly designed by MBB and Kawasaki Heavy industries.

The Intermediate (42 degree box) and the T/R (90 degree box) were lifted from the Bo105 series machines and are manufactured by ZF (ZandfabrikFreidrichafen) in Germany.

The Bo105 used either the ZF72 or the ZF112 main Xmsn depending on the model (and or the military?).

They are all Bulletproof! (providing of course you don't use too big a bullet!!).

Cheers ..... :ok: :ok:

[John Eacott]

ZF: the black hole of gearbox overhaul :( My MGB was lost there for three months, and TRGB for two months :mad: My MGB had to go to EID for overhaul, who then had to send it to ZF, whereupon it disappeared. The TRGB was an even worse drama :rolleyes:

Re the 117 MGB, my understanding is that Kawasaki have the design approval, but (all) the MGB's are assembled by ZF, regardless whether they go into a KHI or a Eurocopter BK. Check any 117 MGB, look for European inscriptions from the production line checks (crossed 7's, funny shaped 1's, etc) by the Inspectors.

KHI having design approval is a nightmare, nothing gets done in a hurry coming out of Japan. European 117's have many advantages over the Japanese built units: eg any KHI service must incorporate ALL previous lower hour services at the same time, ie a 1200 hour must include a 600, 300, 150 and a 50 hour inspection, even if they're done out of sequence :rolleyes: European servicing allows far more latitude, for the same airframe :confused:

[widgeon]

John , how have ZF been for cost ? , if i recall correctly their "standard" overhaul has so many terms and conditions that virtually every box would end up with loads of over and above charges.

[John Eacott]

Widge,

Horrible! The TRGB was returned having seized (on the bench, after removal) witnessed by Eurocopter engineers. After 2-3 months the bill for $US4,000 arrived, "no fault found", pay before we give you your box back. Some terse exchanges resulted in a more detailed inspection, and a repaired GB arrived back without much further explanation. Shortly after, an AD was issued recalling all TRGB's with the bearing that failed on my box :(

Fortunately the Kiwi's are looking like being able to do the overhauls in future :D :ok:

[helmet fire]

Been quiet a while here guys, but I would like to renew discussion on the BK117 pitch up at High AUW/DA/IAS.

Hingeless Rotors and splitpin, you say you have both experienced the pitch up, and splitpin claims it a regular occurence. What interests me here is the cruise power you are setting.

Do you cruise with TQ at 60 matched or 70 matched/top of the green?

The reason I ask is that some of the pilots I have spoken to with considerable BK time (in excess of 3000 hours) have never experienced it, and yet other pilots with far fewer hours have seen it more than once. The only obvious difference I can see that would relate to the pitch up is the TQ settings (High TQ is indicative of higher blade pitch angles and higher forward speed). The pilot's whom have experienced this were using 70% matched or top of the green. The others were using 60% matched for cruise.

To my knowledge, the flight manual, tech notes, training notes, nor checklist indicate that pilots should use any particular TQ setting for the cruise. It seems that from the original German Test pilot who recommended 60% matched, that is the convention here in Oz passed from endorsement to endorsement. Except that some people have not had that exposure, and have no written advice either, thus they are using 70%/top of the green as per every other helicopter.

Has anyone experienced this pitchup below 8000 ft DA, below 70% TQ setting or below VNE - 10kts?

[John Eacott]

HF,

Yes, to all three.

As you said, there is no recommended Tq setting for cruise in the BK, and I have a peculiar habit of using 62%: it's what I used in the S61 and 212, and seems convenient ;) At that setting I've had pitch up at DA's above 5000' in cruise at 120kias, and at lower speeds. Mountain turbulence has been a factor on most occasions, and sometimes my speed has been down around 100kias.

Just one of those things that you learn to anticipate, and live with.

[Oogle]

I also think that the reason for the "lower" Tq settings for the BK (at least in the early years in Oz) was to nurse the LTS101 along a bit easier.

That was when it wasn't working too well - but at least in the BK it was working alot better than the USCG Dolphins and 222's due to the lower output speeds.

The only problem now with using MCP in cruise is that it can get a little thirsty on the fuel and a little too bumpy if you do get alot of turbulence at high speeds.

[helmet fire]

John and oogle, thanks for the replies. Oogle, did you experience the pitch up?

John, I just want to clarify what I mean by the pitch up. I am not talking about pitching due to turbulence ie the pitch rate is uncomfortable, harsh, and "normal" given the fact that you are in turbulence and in a ridgid rotor head. This pitch up is associated with other tubulent movements of rolling and pitching down. And it is controlable with cyclic. IFR ships seem to experience a solid pitch up in turbulence when driven by the autopilot, but this can be overcome easily by cyclic.

I am talking about a pitch up phenomena that occurs quickly and unexpectedly and is not controllable by cyclic alone. It, as far as I can gather from those whom have experienced it, often results in a nose up of more than 40 degrees and can be accompanied by hitting the forward cyclic limit, and can even produce a steady red on the most moment indicator. It seems to be best remedied by reduction of collective rather than persisting with cyclic.

[blade root]

I flew one for about ten years and have never experienced the aircraft pitching up uncommanded.

Though having said that, I flew with a chap who did, and in recovery over pitched nose down. In recovering from the pitch down he took out part of the vertical stabilisers with the main rotor. (He stated the nose up movement felt like going vertical nearly rolling onto it's back)

The pilot involved gave up flying after the experience.

He also associated it with turbulence.

[helmet fire]

blade root,

during your ten tears, what TQ setting do you use in the cruise?

Have you regularly been in DA above 8000ft at near max AUW?

hf

[blade root]

Helmet fire

Very rarely above 1500ft. due to the operational reasons.

Tq in the cruise 50-55% and usually with light payloads.

[Oogle]

Helmet Fire

I have not experienced the pitch up that you mention. Mind you, most of my time up at the altitudes that you mention is enroute IFR. The autopilot has caused a couple of hiccups but nothing to write home about. Fire bombing for a number of seasons but at relatively lower altitudes than you mention.

Certainly the inflow roll problems associated with a low level trun to the right. I have the bruises on my left knee to prove it. You can get the same inflow roll problem (running out of left cyclic) with a steep approach with a wind from the left.

That being said - I love the BK.

:8

[Hingeless Rotor]

Helmet,

I have experienced the pitch up phenomenon around 3 or 4 times in my 2500 hrs BK. All were during IFR operations and normally preceded by a bump due turbulance.

It is quite an insideous little problem that once started you need to react quickly before you go past 20 degrees nose up. When it first happened I put in a correcting input that just wasn't enough and felt as if I was chasing it all the way to the stops.....

It dosn't take long before you can pick when it is going to happen and apply a decent correction to snuff it out.

I normally fly around at 60% tq and matched about 98%nr due to the cycle count issues. Usually we are at Max T/O but only around 4000 DH.

I believe the child flight guys in Sydney (oz) had a ripper of a nose up situation that gave them all the willies.

I have not experienced the problem in any B2's I have flown.


Cheers

[Oogle]

Hingeless

The CF machine IS a B2 :confused:

Are you coupled to the autopilot on all your experiences? If so, I think its a problem with the autopilot. In all the autopilot machines I've flown, you can get the autopilot giving what you mentioned and after some headscrathching, it has always been a problem with the autopilot system. Not necessarily with the aircraft type.

BUT, you never know what an aircraft is going to throw at you!:ooh:

[SASless]

I have flown BK's with and without the pitch and roll sas. The ones without, at high speed about ten knots less than vne, you start to feel a sort of buffeting which is a symptom of the onset of retreating blade stall. If you reduce pict and slow down it goes away. i worked with a pilot that had a violent pitch up(rt=etreating blade stall) of this aircraft twice. The aircrat i flew with the pitch sas never felt like it was on the edge, but that doesn't mean it wasn't. In this ship I once experienced a pitch up of the nose in level cruise flight. I had full forward cyclic, to the stop and it didn't stop until I lowered collective. I think this had something to do with the spas system not working properly. The spas is something of interest read up on it.

[DSpice]

Have any of you done much external cargo wook with the BK117? How does it perform at sea level and at 5000 feet.

Thanks in advance

[John Eacott]

Have any of you done much external cargo work with the BK117?

Lots! Apart from water bombing, we also do a heap of sling load work, both at sea level and in the Australian Alps, which are about 6000 ft AMSL. DA in summer gets up around 8-9000ft, and the BK performs remarkably well, although the change to a 117C tail rotor has improved the capability enormously. Engine power is seldom a limitation, but tail rotor authority was woeful with the original TR blades, often hitting the pedal stop at anything above 80% Tq, when at altitude and below translational lift.

At sea level we can lift 1300kg on the hook with 150kg of fuel without any problems, and at 7-8000' DA a good working load is 1000 - 1100kg, depending on fuel load. We shift quite a bit of concrete in aluminium kibbles during ski field construction work, usually on a 100'/30 metre line: the pilot's seat is too far in from the floor to make it a good VR lifter, but as with all things, you get used to it. The BK seems to lift better the longer the line: on fire work, it certainly pulls water in a Bambi more easily and with less power on a 100' line than with the Bambi on the hook. I don't know why, but I reckon there's a 5% Tq difference between the two.

[helmet fire]

Dspice, can you start another thread on the external load issues, as I would really like to get to the bottom of the pitch up?


John, I am still asking above about the pitch up clarification if you can?

Has anybody experienced this pitch up with SPAS inoperable?

I am wondering if we might list the occurances of this pitch up that we can find out about? Remember I am talking about a pitch up that is not overcome by full forward cyclic unless collective is lowered. I am not talking about the normal ridgid rotor head reaction to tubulence bumping.

I am collecting as much info as possible on this to examine a recent occurance, and would appreciate all your info.

Occurences:

1. Australia in Dec 2005, Japanese BK117 B2. 7000 ft hp, 20 deg C. 3180 kg. 70% TQ. 120 kts IAS. SPIFR autopilot machine but being handflown in SAS mode. Turbulence present, and it ws also preceeded by a smaller pitch up bump that was controllable. Extrapolating chart VNE equals 125 kts IAS in this config.

SASless, can you fill your details in?
Hingeless, can you remember your specifics?
Oogle fire bombing speeds are generally well below VNE, particularly with bambi limits.
Blade root: have you got the specifics of the CF incident?

[Hingeless Rotor]

Helmet,

Yes I can remember the specifics.....

All but one BK I have flown were two pilot so I don't think the autopilot is the problem.

In every occurance it was preceded by turbulence. If you react fast enough, you can counter the effect.

I originally thought it was a SPAS problem, but can't bring myself to blame it as I basically have no idea.

I havn't had a BK do it now for years as I really do believe that you can predict the reaction and put in the controlling inputs to reduce it well in advance, although I have to admit that the input is larger than normal.

Oogle,

Honestly, I think it is a BK issue as apposed to an autopilot one. I have only ever flown one with an autopilot, didn't have any probs with it but I only got to drive it for a short time. I might have to amend my comment on not experienceing it in B2's, now that I think of it, the early occurences may well have been in a B2. The CF story puts that one to rest anyway.

Cheers

[oldbeefer]

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.

[BlenderPilot]

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.

[Oogle]

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 :ouch: - have you posed the question to Eurocopter in Donauworth? I have done that in the past with surprisingly good feedback.

Merry Xmas to all :ok:

[trackdirect]

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!!!

[blade root]

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.

[spinwing]

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 !!! ;)

[rotorque]

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

[Freewheel]

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?

[Big Bucks Bernie]

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 (http://www.eurocopter.com/site/docs_wsw/fichiers_communs/docs/A-3,A4,B1toB2Conversion.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.airliners.net/info/stats.main?id=208[/URL).

[sling load]

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/investigation_reports/2005/AAIR/aair200506614.aspx

[hallaheli]

Hi, Looking for info on the BK117 especially the Kawasaki variant. Any difference between the data plates on the MBB and KHI variants? Thanks

[Elmur]

I'm looking for a BK117 simulator for flight crew training. Does anyone know of one?

[Oogle]

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.

[LGW Vulture]

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.

[Elmur]

If there are no BK117 sims. Is there anything similar i.e BO105 or EC145.

Cheers

[sky2000]

@ 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

[mzgoulden]

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.

[Senior Pilot]

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.

[Big Bucks Bernie]

As a matter of interest, does anybody here know if the yellow attachments on the underside of the belly of this BK-117 (http://www.planepictures.net/netshow.php?id=929332) are auxiliary fuel tanks (combined with a set of flight-steps of sorts)? Google so far is drawing one blank after another...

[Brilliant Stuff]

Nice paintjob!:ok:

[Rotorhead117]

They do look like long range fuel tanks similar to the ERA tanks fitted to some early model Bell 412's... they look good on this BK117 but I wonder if you can fill them with FUEL and TAKE-OFF???

[goose0201]

anybody know of a company running airframe training courses for bk117 or ec145 (engineers) near NZ or Australia? have tried airwork but nothing planned this year and possibly not on the cards next year either.

[spinwing]

Mmmm ....


I can only suggest you try contacting Ted Potts .... wherever he may be atm?

........ (Queensland perhaps?)



:}

[widgeon]

They may be external Oxygen tanks if this is an EMS ship . I recall a couple of STC's that placed them roughly in that position on the BK117

[SawThe Light]

goose0201. Check your pm

[goose0201]

thanks mate but email address did not come through, i replyied with my email address if you could resend to that....... cheers

goose

[Squat switch]

Big Bucks

Yep they are combined foot step and fuel tanks, they feed into the main system but can't be refuelled freom the main system i.e. you have to fill em separately.
If I remember correctly there is a reduced VNE and therefore cruise and a slight increase in fuel consumption due to the extra drag.

The trade off in speed doesn't make them much use on longer transits.

As to the original subject of the thread I too have had the pitch up, this extract from the report to the operator;

Conditions at the time were +20˚c, 6000’ amsl 1015mb , 65% torque with an IAS of 125kts, little turbulence, straight and level with the APs both engaged in SAS mode, fuel load was 220 kg and the AUW was under 3000kg but not by a significant amount. The aircraft was not fitted with any external accessories. Internal load distribution was not considered to be a factor.
After the recovery was achieved it was noted that the AP1 and AP2 captions were illuminated and the following codes were displayed, 1E45 and 2E43 no other captions were noted to have illuminated during the incident.
Earlier in the transit the SPAS caption illuminated for no apparent reason it was selected off for a period and then reselected on with no disturbance or further failure. It was noted that the movement of the cyclic during the reselection of the SPAS was similar to that experienced when the pitch up was experienced and I concluded that there may be a connection to this system with the pith up event.


For those interested it was a C1 which had suffered an number of these events, ECD gave the systems (Hyd, AP/SPAS, Controls and rigging) a full going over and no faults were found.

To regain control I initiated a roll to the left and wingovered out of it so to speak.

[Test Stand Guy]

Hello everyone,
I am very new to this forum, but I have run across this site several times in search for information. I am looking for information on what the input and ouput speeds and torques are for the intermediate and tail gearboxes on the Mbb/Kawasaki BK117. I am looking for these values at 100% rated speed and torque. (not maximum) Any links would be helpful.

Thanks for your help.

[Kulwin Park]

Hi TSG,

Long TRDS speed into IGB = 2396 rpm Input
Intermediate TRDS speed out of 50deg IGB = increase to 2995 rpm Output
90deg TRGB = decrease to 2169 rpm OutputFrom what I remember, that the Squirrel TRDS speeds are 6000/3000 rpm due to coming direct out of rear of engine at module 5, then decreasing to 1800 rpm at the TR. Unsure on figures, long time ago.

Ta, KP

[Test Stand Guy]

First off thanks to the mod. who moved this to where it might get better responses.....

KP,
Thanks for the information. You don't have any idea of the torques associated with those rpms do you. (or HP and I can calculate torque).

Thanks
TSG

[Pilot13A]

Hi, Does anyone have experience on the C1's, do they have CAT A profiles for other than clear helipads and if so is a min distance stated. They appear to have good OEI performance, very close to the Airwork 850D figures without the expensive mod required. Our company is considering an IFR one as a multirole SAR/EMS ship. Any thoughts guys/gals??:hmm:

[Kulwin Park]

Sorry TSG. No idea of torques. I'll see what I can dig up ... maybe another week before back though. Cheers

[Bell_209]

Honeywell has comparative figures for BK117B-2, C-1 and the LTS101-850D mod. The -850D performs much better than all of them. There's a couple now flying in Sydney with the mod and they're happy with it - neither C-1 nor the -850D has an increased MTOW, though; so you still can't carry payload AND fuel...

C-1 OEI is much better than the B-2 (on paper). It's the real AEO figures you need to worry about...

[skiper-choper]

Hello everybody. I need the FLM and the familiarization manual, C1 version. Engine Arriel 1e with honeywell DAFCS. If anyone need, i have the full EC-135T2+ FLM + familiarization manual. Thanks a lot!!!!

[skiper-choper]

ec-135t2+ for clear heliport
tomorrow i`ll post bk info

DEFINITIONS
- Takeoff Decision Point TDP . .20 ft130 KlAS
- Landing Decision Point LDP 80ft 40 KIAS/
300 RD < 500 fl min

8.2. LiMlTATiONS (IN ADDITION TO THE LIMITATIONS GIVEN IN PART A, "GENERAL")
8.2.1. CERTIFICATION CRITERIA
The definition given below are related to the respective emergency and normal procedures

- A surface level heliport, certified for day and night operations, with
minimum field size of a minimum field length defined by the takeoff and landing distances
of this chapter and a minimum field width of 15 m.

[landseaair69]

Had a BK 'moment' the other night....

During a fully coupled ILS approach, practice for currency under VFR conditions otherwise would have been even more disconcerting...
Tracking down the ILS nicely until we go over the Outer Marker, as soon as we get the lights and audio we get a 10-15 degree pitch up, we decoupled the AP after it showed no signs of trying to regain glideslope after a couple hundred feet....
Spoke to another operator and they had the same thing in their BK, but not their B412....
There is a radio mast just left of track, possible signal interference....???

Thoughts....

[Flying Bull]

Hello LandSeaAir69,

that is a fairly commen experience in the BK117 - had it with differnt machines - always at the same position.
Some airports are more prone to this behavior than others.
It´s an very old computer in the autopilot......
Just be prepared while on the ILS, especially passing the OM - and either go around or reset the AP

Greetings Udo
"Flying Bull"

Hi,
me again - had a talk to a fellow pilot - it´s actually not the OM causing the disturbance, it´s the RAD-Alt setting in - which is about 2000 feet (on some places the position of the OM)
So have a look on the RAD-Alt or knowing where you pass the 2.000 feet, to be prepared!

[BigMike]

Hi, is there a differences paper or training manual for the above?
Looking for an official training manual for the C1 if possible.

Cheers BM

[Flying Bull]

Hi, is there a differences paper or training manual for the above?
Looking for an official training manual for the C1 if possible.

Cheers BM

Hi, there must be, cause I had the training - but it´s a while ago.
I try to catch one from the trainings department and ask him.

Bye the way, anyone interested in buying 1 to 3 BK117C1?
roughly between 5600 and 6000 hrs, 13.000 to 14.00 landings, NVG - cockpits

Greetings Flying Bull

[Flying Bull]

Hi BigMike,
the last difference training was quite a while ago, so no papers just at hand.
From memory,
You need some theoretical part, covering the engines, especially the overspeed protection, possible different copckpit layout (Fuel-shut-off-lever-assembly, different switch- and fuse panels), VARTOMS (variable Rotorspeed and TQ Matching system)
as well as an smal amount of flying.
Greetings Flying Bull

[Phoinix]

Hey FB!

Are these medical equipped, hoist? What BEM are we looking at? Thanks!

[Flying Bull]

Hey FB!

Are these medical equipped, hoist? What BEM are we looking at? Thanks!

Nope - no medical equipment and no hoist - police role - wires for FLIR and WESCAM

[Phoinix]

Nope - no medical equipment and no hoist - police role - wires for FLIR and WESCAM

Right, thanks. Without the camera and flir; below 2000kg BEM?

[Flying Bull]

Right, thanks. Without the camera and flir; bellow 2000kg BEM?

not quite...
TCAS, wires, long nose, sound proofing and some other added a little weight

https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/1049x721/b7a525a7_9dec_42b7_a25a_95fe3e1c2118_1674f4d6a0a4f889c36c042 a4ea20aa9adcce547.jpeg
BK C1 weight

[Phoinix]

Thanks for the help. Looking for a ballpark estimate.