Seems to be true for piston engines.

Buy one 300 HP engine, or two 150 HP engines, about the same total price.

When things are made in small batches, building twice as many is *way* less than twice the cost. Most of the build is setup cost.

Combine twice as much volume, parts that are smaller, yes, the two smaller engines can be the same price as one larger.

Especially when you include the various other factors such as insurance, development amortization, support, certification, etc.

Mike C.

Not on an OEM contract.

Cessna didn't ship a $3M airplane with $2M of engines on it.

Mike C.

Seems to be true for piston engines.

Buy one 300 HP engine, or two 150 HP engines, about the same total price.

Mike C.

So, then a single engine is cheaper! Thank you for confirming this!

Tim

1. Smaller is cheaper to make. Less materials, made on smaller machines, easier assembly, etc.

2. An engine on a single is higher liability. Selling one engine means all liability is included in one engine cost.

3. Selling half as many engines means twice the amortized development and support costs per unit.

4. Selling only one engine means only one engine program payment and loss of future recurring revenue.

An FJ44 is really a far more expensive engine than a PW610F.

The Eclipse bankruptcy exposed the contract with PWC for PW610F engines. Eclipse was getting them at ~$280K each in 2008. That's about $320K today using CPI-W.

I doubt you can buy an FJ33-5A for twice that.

Mike C.

The PW610F on the Eclipse EA500 is 900 pounds thrust each, 1800 pounds total.

The FJ33-5A on the SF50 is 1846 pounds thrust.

The twin engines are less than half the rating of the single engine on the same weight airplane. The EA500 goes higher, farther, faster, on less fuel. It also climbs when an engine fails.


SETP engines have independent shops that can do HSI and OH.


No independent shops for FJ33 work, Williams makes out of contract HSI and OH more expensive than being on program.

Mike C.

Eclipse is meaningless info. I said "Mustang"

A Mustang engine is 80% of the SF50 engine thrust. Nobody ever told me engines are sold by $/lb. of thrust. That’s a new one. Sure, bigger engines cost more than smaller engines, but that’s a really general statement.

this thread is turning into a train wreck and I have to keep watching

It turned into a train wreck a few years ago. It's in it's death throes now.

1. Smaller is cheaper to make. Less materials, made on smaller machines, easier assembly, etc.

2. An engine on a single is higher liability. Selling one engine means all liability is included in one engine cost.

3. Selling half as many engines means twice the amortized development and support costs per unit.

4. Selling only one engine means only one engine program payment and loss of future recurring revenue.

An FJ44 is really a far more expensive engine than a PW610F.

The Eclipse bankruptcy exposed the contract with PWC for PW610F engines. Eclipse was getting them at ~$280K each in 2008. That's about $320K today using CPI-W.

I doubt you can buy an FJ33-5A for twice that.

Mike C.

Really? Running a Willliams turbofan off program? Bold!

So far, the second hand ones I've seen have all been on the program. The program is all inclusive of airframe maintenance, engine program and training. Buy the plane, insurance, hangar, gas and the program covers everything else.

@200hrs/yr, it's $333/hr.

https://cirrusaircraft.com/jetstream/

The one, the only data point he has is Eclipse. Which collapsed taking billions of investor dollars with it. It's rather like claiming it's possible to make 12% per year on the stockmarket every year because Bernie Madoff did it. So yeah, I guess if you can get someone to write off billions into your project that you don't have to make a profit or pay back then sure, it can be done. But not otherwise.

In the real world, no new piston twin (Baron, Twin Comanche, Seneca) was ever cheaper than the equivalent single (Bonanza, Comanche, Saratoga).
No new PT6 twin was ever cheaper than the equivalent single.
New quad jets are more expensive than twin jets even on the same airframe (A340 vs A330).
And no modern company has ever made a twin jet equivalent to (no jet Cri-Cri, here) and cheaper than the SF50 and survived.

You would say the same for all the information present in classes in business school.

You can call it an "assumption", but building twice as many smaller things does cost way less per unit, and that is borne out by industry every day.

Mike C.