hums

[widgeon]

HUMS has become quite a buzzword in the community. To any of you using HUMS equipped helicopters in general what effect has it had on maintenance costs ?. I know in theory it is supposed to detect small defects before they become major and reduce the overhaul/repair costs but in practice is this the case ?. Will the engine manufacturers increase TBO on HUMS equipped aircraft ?

[Kwikfitter]

Widegon,

We use it on nearly all our machines.

It still isn't at the stage of extending TBOs etc, but has stopped some vibration checks that had to be done periodically, i.e. High Speed shaft checks on S61s and monitoring the 332 ones. It's reduced the vib levels significantly on the 332, so reduce the problems associated with that. It does track and balance every flight and you can do adjustments based on the redaings. Post Maintenance Inflight Tracking is also easier and quicker.

It has made the machines safer since now exceedances are recorded to the Nth degree, no longer was it about 850 ITT for a few seconds, it was 897 for 48 seconds. So we now know a lot more about whats happened.

Initally it was a pain but now it's just another piece of kit that is Mandatory on North Sea Machines.

Helps us anyway

[Fool on the Hill]

Why use HUMS.
If it dosnt rattle, vibrate and cost afortune to maintain its not a helicopter. :D

[baranfin]

Hi guys, I would just like some clarification. I am assuming that HUMS is some sort of vibration monitoring equipment? but you all know what happens when we assume.
thanks alot.

[helmet fire]

Baranfin:
I believe HUMS is Health Usage Monitoring System. It is not restricted to any one parameter (such as vibration). It could be combinations of engine temps/speeds/fuel flows/hours/starts/power assurance/etc, rotor vibrations/speeds/hours/stresses/usage/etc, airframe stressors/vibrations/usage/weights/airspeeds/landing forces/rollrates/etc, transmission torques/powers/vibrations/shaft speeds/shaft vibrations/etc. And heaps more.

They can be comprehensive, such as those on the North Sea, or simplified such as an Engine Trend Monitor (ETM) which is relatively cheap (US$15 - 20K) and simple.

I have heard that an ETM for a B212/B412 increases TBO on the PT6 by 1000 hours. Can anyone confirm this?

[disstings]

If I joined a company now without HUMS I'd ask the chief engineer why he hasn't got it. If he was then indifferent about it, I would have great pleasure in approaching the board and then instigating it.
Where I've worked, it's saved a few guys catastrophic engine failures , and even gearbox early warnings. It'll also check tail rotor problems and make you tea in the morning.

DO NOT BUY A HELICOPTER WITHOUT IT!

[Lu Zuckerman]

Regarding HUMS I became familiar with the concept as it was built into the dynamic systems of the EH-101. The only problem I can see with it is that the vibratory temperature limits and acoustic parameters that are programmed into it are developed under controlled conditions. This black box is then installed into a helicopter that may have several thousand operating hours. If the programming does not cater to the older helicopter that may be perfectly good but it is operating at higher temps, higher vibratory levels and generating acoustic patterns that are close to the allowable limit for a new helicopter but still be perfectly acceptable for a helicopter with high hours and my assumptions are correct the HUMS system will result in a high pull rate of dynamics components that are still serviceable. But then again, what do I know?

[Nick Lappos]

HUMS is the first great step in tightly connecting the manufacturers to the users. While it is just a monitor and vibe balancer in many current installations, that is a good start. As we all get more comfortable, it will become the daily link between the aircraft and the designer, so we at the factory will know what is being experienced in the field on a daily basis.

Regrading the Lu's question of how to relate the lab tests with the actual field dtat, by reading the HUMS ifo regularly, we can relate the two almost daily. We also bring back items that have reached their time limits, or that have been flagged by the HUMS (as having unacceptable vibes or temps) and test them in the lab to correlate the findings.

I am the S-92 program manager, and have asked that we get to the point that the aircraft, the maintenance hangar and the manufacturer of the components and Sikorsky all be tied together in a network, so that actual experience is shared by all, and that the maintenance procedures be made adaptive to the operator, his usage and his environment. The S-92 has a maintenance diagnostic computer tied to the HUMS, as well as a bearing monitor unit, all to let the aircraft report its state to the system. Eventually, I would like to see SATCOM real time links so the info was immediate (talk about Big Brother!) :p

[baranfin]

Thanks for clearing that one up for me. This forum is a great source of info. I'd just like to tell everyone to keep it up. thanks again.

[The Sultan]

Nick,

HUMS has been sold as the end-all/see-all monitor for the aircraft. If this is the case, why does the S-92 need a supplementary bearing vibration/temp monitor (which from what I have seen your $250K Goodrich HUMS system should do)? Could it be Level B?

The Sultan
:rolleyes:

[Nick Lappos]

Sultan,

And the Bell 412 has what? ;-)

Seriously, the system grew up while the S-92 aircraft did, so it comprises three black boxes, the BMU, the HUMS and the Maintenance Diagnostic Computer. They all share info, so they could be considered a distributed solution to the total HUMS/Maintenance set of issues.

Curious, what will the 609 have?

[CTD]

That's a secret :D

I noticed the wink, but just in case you're interested for real, the Canadian Forces 412s are HUMS equipped (Stewart Hughes/Teledyne) and monitor vibration levels on rotors, all external bearings, Main Drive Shaft, all gearboxes, along with speeds (N1 and Np), Qs, Ts and Ps, usage etc etc.

Is Sultan who I think it is Nick?

[Flight Safety]

CTD, I think Sultan is a Bell employee.

To Nick,

Regarding the SATCOM question for the S-92, is your idea basically to provide real time information from the HUMS to both the operator's maintenance facility and to Sikorsy Support, while the helo is still in the air? I assume you're thinking that the operator's maintenance personnel can consult with Sikorsky support and have a maintenance solution available ASAP after the helo lands. This with the idea of reducing the non-scheduled maintenance turnaround.

If this is what you're thinking, I think it's a great idea.

(Edited for spelling)

[ 27 August 2001: Message edited by: Flight Safety ]

[Nick Lappos]

Flight Safety,
Yep, wish I could claim credit, but I understand that lots of Big Iron does it already. Why not? At 300 mill a pop, the interest spent on the investment is about $3500 per hour!

The SATCOM is future plans, not initial delivery. We have to walk before we run. :cool:

[widgeon]

I was wondering if Rolls Royce were monitoring the Transat that flamed out ? , although if you are not getting fuel to the engine no amount of maintenance is going to help you.

[widgeon]

Smiths Aerospace to Supply Sea King HUMS
Posted Monday, August 27, 2001 by News Staff

The Ministry of Defense has awarded Smiths Aerospace a $57 million (£40million)contract to design and install their Generic Health and Usage Monitoring System(GenHUMS)to its fleet of Sea King helicopters flown by the Royal Navy. The MoD currently operates 90 Sea Kings of various models. The systems will be designed and manufactured at the Smiths facilities in Southampton, UK and Grand Rapids, MI. Deliveries begin in 2004 with completion in early 2007.

Bob Ehr, president of Smiths Aerospace, Electronic Systems business said: "Our HUMS solution represents the latest technology, developed and proven in over one million flight hours of real world operations. The integrated system offers both improved safety and reduced operating costs for a variety of helicopter platforms."

The GenHUMS system is an integrated cockpit voice and flight data recorder with a health and usage monitoring system, installed on each aircraft as a "single box" system. It continuously checks the performance of safety-critical components, providing advance warning of potential equipment failures and collecting valuable data for routine maintenance of the helicopters. It provides sensors that monitor the status and usage of the engines, transmission, drivetrain system, rotor system and airframe by detecting and diagnosing potential failures, monitoring usage, automating test procedures and providing alerts for potential maintenance actions.

Smiths Aerospace is the prime contractor to the MoD for all contract activities. This includes tailoring the system to various models of the Sea King, aircraft trial installations, system verification, and airworthiness approvals. Half of Smiths Aerospace's 12,000 staff and $2 billion revenues are located in North America. The company holds key positions in the supply chains of all major military and civil aircraft and engine manufacturers, and is a world-leader in electronic systems, acutation systems and precision components.

From www.rotor.com (http://www.rotor.com)

[Lu Zuckerman]

The DC-10 was originally designed with a type of HUMS system. The system would record data and any deviation from programmed values would be downloaded via a data link and the replacement part or the necessary system maintenance would be waiting for the aircraft when it landed. In just about every case every single installation was removed to both simplify the systems reduce weight and to minimize false pulls due to erroneous indications of the monitoring systems.

[The Sultan]

Nick,

As stated earlier the 100 412CF's were equipped with HUMS as part of the original production configuration. Commercially, few customers see a need for HUMS as the 412 is the model of a safe and reliable vehicle.

Relative to the 609: the basic aircraft has a Collins Maintenance Diagnostic Computer for system monitoring and fault recording and a bearing monitoring system for primary bearings not in the oil lubricated gearboxes. The difference is that when the HUMS goes in the bearing monitor comes out as our HUMS also does the critical bearing monitoring.

The point of my professional interest is that if you have a HUMS why does the S-92 have a supplementary bearing monitor? Is it due to the software criticality level or some other FAA mandated reason?

What MDC are you using? We are using the Proline 21 MDC. It has been a lot of "fun" to develop. We now have it purring away quite nicely. Hows is yours coming?

In the old days when Bell and Sikorsky had a common interest like when we developed the RADS together (at the worker level, we did not tell our respective management) we were able to share useful insight on what needed to be done to achieve our end goals. Too bad we can not do that today in the area of diagnostic systems. (Yes I know there are forums, but they are pretty well monopolized by those trying to sell and those trying to justify what they bought. Very little useful data flows which furthers the industry.)

The Sultan

P.S. Tell Tommy hi and that Jay Miller has moved to Seattle (though I am sure he knows).

:D

[Nick Lappos]

Sultan:

>>>if you have a HUMS why does the S-92 have a supplementary bearing monitor? Is it due to the software criticality level or some other FAA mandated reason?
NL: Not really, as the HUMS has level B too. The BMU came first, then the HUMS and then the MDC, sort of crept up on us.

>>>What MDC are you using?
NL: We are using a Collins DCU and writing the code ourselves.

>>>In the old days when Bell and Sikorsky had a common interest like when we developed the RADS together (at the worker level, we did not tell our respective management) we were able to share useful insight on what needed to be done to achieve our end goals. Too bad we can not do that today in the area of diagnostic systems.
NL: Boy, you are right! It would go easier if we developed a common set of boxes, shared code and just got on with it.
Give me a call and we can try!
:cool:

[400 Hertz]

Anybody who'd like info on the BAE IHUM system fitted to the N Sea aircraft can turn to http://www.hums.com/humsindex.htm

They have about 150+ aircraft fitted worldwide. S61/S76/AS332/Bell 212/Bell 412/ AS365.

Another site of interest may be http://www.shl.co.uk/Technologies/Pages/homp.htm as this is the FDR data recorded in real time, fed from the IHUM system.

And I never mentioned pilots pay once.