Do we need bigger amphibian water bombers? (2 Viewers)

[Engineman]

Hi,
Of course, you can write the scenario's to match any scenario-optimised waterbomber, from a flying flea with a 5gal bucket to an A380 derivative with 100Tons! However, I think the general need is a flexible mid-size amphibian with proven capability, and with good economics. Beyond that, I do feel that their are some basic features that should be considered for the sake of the crews and their operating environment. Firstly, other than for very short duration/range tasks, crews should be minimum 2-pilot. Secondly, I would not be happy with single engine types at all and I think their overall capability/cost/safety equation should rule them out of realistic consideration for all but the specific tasks that they suit. My last thought is that whatever platform is considered , it should be capable of pulling 4G due to the harsh environment. It is no good claiming that Captain Smooth Big-Balls can cream on in to a canyon in perfect conditions in his ex-airliner without spilling his coffee, but come the day that he has to PULL-HARD! to miss that hidden ridge or the rising ground visual illusion, you need a tough aircraft!
Just my view after surviving years at low level.

Eng

 

[Shortround6]

Large fires can create their own local updrafts and down drafts. Combine with low visibility (smoke) and needed to split vision between outside the cockpit and inside (ground mapping radar?) and things look like they can weird very quickly.

And sometimes you really need to put a lot of water in a small area quickly. With some fires you spend a lot of time looking good for the cameras until the fire burns itself down to the size fire your rate of water application (gallons per minute) can actually put out. I was involved with several lumber yard fires with 2-3 water cannon capable of putting out over 500gpm (1900 l/m) minimum and needing a number of hours for the fire to get small enough so that the water flow could put the fire out. We kept it from spreading, we didn't make much headway.

 

[skyking1]

Hi,
Of course, you can write the scenario's to match any scenario-optimised waterbomber, from a flying flea with a 5gal bucket to an A380 derivative with 100Tons! However, I think the general need is a flexible mid-size amphibian with proven capability, and with good economics. Beyond that, I do feel that their are some basic features that should be considered for the sake of the crews and their operating environment. Firstly, other than for very short duration/range tasks, crews should be minimum 2-pilot. Secondly, I would not be happy with single engine types at all and I think their overall capability/cost/safety equation should rule them out of realistic consideration for all but the specific tasks that they suit. My last thought is that whatever platform is considered , it should be capable of pulling 4G due to the harsh environment. It is no good claiming that Captain Smooth Big-Balls can cream on in to a canyon in perfect conditions in his ex-airliner without spilling his coffee, but come the day that he has to PULL-HARD! to miss that hidden ridge or the rising ground visual illusion, you need a tough aircraft!
Just my view after surviving years at low level.

Eng

That is one of the reasons I like the Fire Boss. Crop dusting is a steady diet of high G pulls and those planes are built for it. We'll just have to disagree on single engine Ops with the PW-6 engines. One, two or 20 they log millions of hours between failures across the fleets.
There is a seat for a RIO in that one in the video, with controls.
As for the cost:
The Boss is roughly 4 Million per unit.
It hauls 3100 liters.
The CL-415 is roughly 37 Million.
It hauls 6100 liters.
This is not difficult maths.
Then you add in the myriad of possible loading sites that the Boss can negotiate that the bigger planes cannot, and the liters/hour on the fire can go away up.

 

[Engineman]

That is one of the reasons I like the Fire Boss. Crop dusting is a steady diet of high G pulls and those planes are built for it. We'll just have to disagree on single engine Ops with the PW-6 engines. One, two or 20 they log millions of hours between failures across the fleets.
There is a seat for a RIO in that one in the video, with controls.
As for the cost:
The Boss is roughly 4 Million per unit.
It hauls 3100 liters.
The CL-415 is roughly 37 Million.
It hauls 6100 liters.
This is not difficult maths.
Then you add in the myriad of possible loading sites that the Boss can negotiate that the bigger planes cannot, and the liters/hour on the fire can go away up.

Hi,

I did allow for other possible options, both big and small,
"Firstly, other than for very short duration/range tasks, crews should be minimum 2-pilot. Secondly, I would not be happy with single engine types at all and I think their overall capability/cost/safety equation should rule them out of realistic consideration for all but the specific tasks that they suit."
The reason that I don't really like the thought of single engine Fire-Fighting is that the crew has little chance in the event of engine failure in inhospitable areas, which is often their operating environment. Certainly, a Multi-engine aircraft is not immune to engine failures but, as a multi engine Fire-Fighter it should built with real single-engine safety of continued flight capability, something a single engine aircraft never has.
Yes, the PT6 core engine has a very high reliability. However, the real world MTBF of a complete single PT6 power system including all ancillaries and external factors seems to be around 8,500 to 15,000 hours from a search.

Cheers

Eng

 

[skyking1]

We flew single engine SAR in the mountains of Washington, Oregon and Idaho. You figure on about 45 seconds from when it coughs to touching trees at best. It was a risk we took and I would do the same for fighting fires.
Most of the time I flew high bird in the C310 and provided the aircrews with a lifeline in the event of a loss of power.
The weather was rarely good when a plane went down in the mountains, and they liked sending me above the clouds on those days. We'd zoom on up to 11K and loiter for 6 hours, moving coffee from the thermos to the coffee can.
I tried getting on with the forest service as a lead plane pilot but was "too old" to get started at 38. I don't think they considered pilots who came up through civil aviation at that time.

 

[Engineman]

We flew single engine SAR in the mountains of Washington, Oregon and Idaho. You figure on about 45 seconds from when it coughs to touching trees at best. It was a risk we took and I would do the same for fighting fires.
Most of the time I flew high bird in the C310 and provided the aircrews with a lifeline in the event of a loss of power.
The weather was rarely good when a plane went down in the mountains, and they liked sending me above the clouds on those days. We'd zoom on up to 11K and loiter for 6 hours, moving coffee from the thermos to the coffee can.
I tried getting on with the forest service as a lead plane pilot but was "too old" to get started at 38. I don't think they considered pilots who came up through civil aviation at that time.

Sorry to hear that your aspirations at 38 were blocked!
I think that no one should doubt the dedication and bravery of Emergency services workers! My words here are merely to recognise the realistic risks that some operations face and to
encourage the reduction of those risks where possible by defining them and the equipment that they are allowed to use.
Possibly, the additional risk to single engine Fire Fighters could be balanced with the provision of lightweight ejection seats?
Overall, I do not want to see penny-pinching contracts that make money because dedicated crews take extra risk.

Eng

 

[Shortround6]

There is a need for a number of varied sized fire-fighting aircraft. One size does not fit all.
There is a real problem with production.
Fires are getting bigger; the fire season is lasting longer and there are more fires active at the same time. A real triple wammy for the fire service aircraft

Sometimes helicopters are the best you can do. Can refill from much smaller water sources and/or closer to the fire. But smaller load per drop and often need to refuel more often.
Moving the helicopters long distances is difficult.
The Cl-415 can self-deploy (ferry) about 2400km or slightly shorter stages.
CL-415 advertises about a 1200ft shorter scoop run (about 50ft down to scoop and then 50ft back up than the Fire Boss.
Height above sea level and air temperature may change that.

What is really amazing is that most of the world is depending on about a 60 year old basic airframe design for the big twin and a 36 year old agriculture aircraft for the Fire Boss.

Governments are going to have to decide on many things. More air support or more ground vehicles and ground crews and/or a good mix.

 

[Engineman]

What is really amazing is that most of the world is depending on about a 60 year old basic airframe design for the big twin and a 36 year old agriculture aircraft for the Fire Boss.

I don't think that it is amazing. The basic 215/415/515 has been developed and improved. The basic airframe is not a slippery composite form because it needs to be a simple, reliable and rugged machine. The aerodynamics are optimised to get the job done and remember, that includes water/land/air and scooping. I would be interested in the "improvements" that
could be made without increasing the operating cost, compromising the flexibility or increasing the price?
Overall, possibly a big factor might be the shorter transit times for long range deployments, but for that long range/time critical case, won't the availability of some ex-airliner Fire-Fighters always have the deployment speed advantage? What cost the M 0.7 capable amphibian/scooper?

Eng

 

[Shortround6]

What cost the M 0.7 capable amphibian/scooper

Well, M 0.3 might cut transit (ferry) time by 1/3rd. Going faster might be diminishing returns. I don't know where the sweet spot is.
They have been doing improvements that they can while keeping the cost of retooling to a minimum.
This is what happens when the orders come in with dribs and drabs.

Unless people believe that forest fires are going to diminish significatly in the next few years and stay at low levels for decades after that, better fire fighting aircraft are needed.

 

[Admiral Beez]

I think the general need is a flexible mid-size amphibian with proven capability, and with good economics. Beyond that, I do feel that their are some basic features that should be considered for the sake of the crews and their operating environment. Firstly, other than for very short duration/range tasks, crews should be minimum 2-pilot. Secondly, I would not be happy with single engine types at all and I think their overall capability/cost/safety equation should rule them out of realistic consideration for all but the specific tasks that they suit. My last thought is that whatever platform is considered , it should be capable of pulling 4G due to the harsh environment.

Of all the DHC alternatives, sounds like the Hynaero Frégate-F100 meets all your criteria.

 

[skyking1]

Sorry to hear that your aspirations at 38 were blocked!
I think that no one should doubt the dedication and bravery of Emergency services workers! My words here are merely to recognise the realistic risks that some operations face and to
encourage the reduction of those risks where possible by defining them and the equipment that they are allowed to use.
Possibly, the additional risk to single engine Fire Fighters could be balanced with the provision of lightweight ejection seats?
Overall, I do not want to see penny-pinching contracts that make money because dedicated crews take extra risk.

Eng

That is not a bad idea. It would require additional training for it to be a safe alternative, but wrap that into the purchase costs.

 

[Engineman]

That is not a bad idea. It would require additional training for it to be a safe alternative, but wrap that into the purchase costs.

Yes, the ejection seat does introduce some cost and training demands. For a system that functions in the operational envelope of a single turbo-prop Fire Fighter, it might not be too complex, although I would say a dynamic performance of Zero/Zero would be required for the slow/low alt likely scenario. Such performance would likely need a rocket assisted seat, but that is quite normal in bang seats.

Eng

 

[swampyankee]

That is not a bad idea. It would require additional training for it to be a safe alternative, but wrap that into the purchase costs.

One problem may be that the pilot may be ejecting into an active fire.

As an aside, aerial firefighting is one of those jobs that makes "commercial pilot" up there with "commercial fisherman" among the jobs most likely to get you killed.

 

[swampyankee]

But it is "readily" available.

Is there any doubt? Of course it will continue. It's no longer possible to save stupid humanity. Maybe it's for the best...

Hell, we've got groups actively encouraging making it worse.

The long-term drought that's largely the reason for worsening fires in the Western US (this may extend into Canada; the US media had always been parochial, but it's now approaching active isolationism, and I don't have that information at hand) is in the process of making the current population of the western US states unviable.

 

[swampyankee]

Is there any doubt? Of course it will continue. It's no longer possible to save stupid humanity. Maybe it's for the best...

Hell, major ideological groups in one major First World country are actively promoting it.

 

[Admiral Beez]

aerial firefighting is one of those jobs that makes "commercial pilot" up there with "commercial fisherman" among the jobs most likely to get you killed.

I ran a quick Ai check, FWIW.

"The Bureau of Aircraft Accidents Archives records 32 CL-215 accidents and 50 fatalities. For the CL-415 it currently lists 9 accidents and 12 fatalities, although other compilations count 14 CL-415 aircraft destroyed, because they use a broader definition of losses/accidents. The older CL-215 accounts for most of the losses. Of only 125 produced, roughly a quarter have been involved in serious accidents over more than 50 years of extremely demanding operations. The most recent high-profile fatal CL-215 loss was the Greek Air Force aircraft that crashed at Karystos on 25 July 2023, killing both crew. The CL-415 has a noticeably better record, despite doing essentially the same hazardous job."

I have to agree with your assessment. Though to be fair this recent loss is not the aircraft's fault whatsoever.

 

[cvairwerks]

I deal with zero-zero seats almost every day. There's a heck of a lot of stuff involved in it, besides just the seat installation. You also have to have a canopy remover system that is tied to the seat pyro system. The canopy system has to have a dedicated secondary pyro initiation system on top of the seat intitator. You need auto-disconnect for radio harnesses and any other system that ties the pilot to the aircraft and has to be shed during an ejection. Have a 2 place cockpit and it gets even more complicated on the installation and systems.

Each seat design has to be qualified to the airframe design. Change the cockpit, the canopy or the pilot interconnect beyond a certain amount and you now have requalify the entire system. Pyro and chutes have inspection and repack time limits. USAF is in a real bind as many of the ACES 2 seat pyro items are lifeing out and there are no current replacements.

Now, since these would be in the civilian world, you need various BATF licenses, hazmat plans, explosive handling and storage plans, operational limitations and so on. I spend quite a bit of time every year requaifying on seat maintenance, explosives care and handling, ESD control and safety as well as certain other funtions with the seat that I have to deal with. I hold an inspection certification as well as seat removal and installation certifications for the ACES 2 and various maintenance certifications on another current seat. On the 2nd seat, I can work on it in the aircraft or on a seat dolly, but can't inspect it for installation, remove it or install it in the aircraft.

Canopy removal systems are a whole 'nother bunch of certifications I hold as well. More explosives stuff........

 

[ThomasP]

A couple of bits of information.

My understanding is that the weight per installation of an ejection seat (ie the seat, the mounting and reinforcing structural bits, and the exit path clearance bits) requires a minimum of about 400 lbs per crew member.

Large fires create their own air currents. There was a study done back in the late-1960s in reference to the Smoke Jumper and ASR units that indicated a high risk for anyone in a parachute anywhere near the fire being sucked into the updraft created by the fire. The study concluded that it was very likely that the standard chute materials of the time would burst into flame or melt (depending on the type) and that even if the chute survived, the heated air in the updraft would kill the crewmember. It was concluded that any crewmember attempting to jump from any aircraft (stricken or otherwise) would need full coverage fireproof suits & headgear, an oxygen supply, and a chute able to survive the high temperature environment.

 

[Engineman]

One problem may be that the pilot may be ejecting into an active fire.

This may be true, however I am proposing the concept of survival from an immediate crash and not always in the delivery zone. IMO it may be better to have 2-pilot 2-engine rugged aircraft from the start, but if the single engine provider has a defining capability, albeit with a quantifiable increased risk, then maybe ways of reducing that risk should be persued.

Eng

 

[Engineman]

I deal with zero-zero seats almost every day. There's a heck of a lot of stuff involved in it, besides just the seat installation.

I am guessing here, that you are working with current or legacy Military escape systems? These are predominately complex systems for very high speed combat aircraft.

You also have to have a canopy remover system that is tied to the seat pyro system. The canopy system has to have a dedicated secondary pyro initiation system on top of the seat intitator.

Low speed perspex canopy arrangements are much lighter than most fast-jet canopies and ejection-through is likely an option or at worst MDC.

You need auto-disconnect for radio harnesses and any other system that ties the pilot to the aircraft and has to be shed during an ejection. Have a 2 place cockpit and it gets even more complicated on the installation and systems.

Seat QD couplings are standard, likely only an RT lead or possibly also Qxy, but no issues compared to modern high-spec Mil kit.

Each seat design has to be qualified to the airframe design. Change the cockpit, the canopy or the pilot interconnect beyond a certain amount and you now have requalify the entire system.

Pretty much standard for aircraft.

Pyro and chutes have inspection and repack time limits. USAF is in a real bind as many of the ACES 2 seat pyro items are lifeing out and there are no current replacements

Agree, a recurrent problem. However, standardisation of equipment for a system/family should help.

.

Now, since these would be in the civilian world, you need various BATF licenses, hazmat plans, explosive handling and storage plans, operational limitations and so on. I spend quite a bit of time every year requaifying on seat maintenance, explosives care and handling, ESD control and safety as well as certain other funtions with the seat that I have to deal with. I hold an inspection certification as well as seat removal and installation certifications for the ACES 2 and various maintenance certifications on another current seat. On the 2nd seat, I can work on it in the aircraft or on a seat dolly, but can't inspect it for installation, remove it or install it in the aircraft.

Indeed. Qualified engineers would be needed. This is really a job opportunity.

Canopy removal systems are a whole 'nother bunch of certifications I hold as well. More explosives stuff........

There are aspects to this. However, as said, I do not see lightweight canopies as a huge engineering problem, if treated seriously from the outset!

Cheers

Eng