Engines for ETOPS
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From: Estonia
Engines for ETOPS
Which planes can apply for ETOPS?
Twinjets can apply for ETOPS over 60 minutes, from 75 to 207 minutes - and if the airframe, engine and airline qualify, they can get it.
Are nonjets permitted to apply for ETOPS? Say, a twin turboprop - if the engine, airframe and airline meet the necessary qualifications, are they allowed to fly under ETOPS?
And what about other engine types? Like piston of wankel twins - can they apply for ETOPS?
And what about trimotors? Trijets can fly arbitrarily long routes without any extra ETOPS limits, but propeller aircraft need 4 engines for long-haul without extra qualifications. Can trimotors apply for ETOPS?
Are geared turbofans classed as jets or as turboprops? What about propfans?
Twinjets can apply for ETOPS over 60 minutes, from 75 to 207 minutes - and if the airframe, engine and airline qualify, they can get it.
Are nonjets permitted to apply for ETOPS? Say, a twin turboprop - if the engine, airframe and airline meet the necessary qualifications, are they allowed to fly under ETOPS?
And what about other engine types? Like piston of wankel twins - can they apply for ETOPS?
And what about trimotors? Trijets can fly arbitrarily long routes without any extra ETOPS limits, but propeller aircraft need 4 engines for long-haul without extra qualifications. Can trimotors apply for ETOPS?
Are geared turbofans classed as jets or as turboprops? What about propfans?
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From: On a good day - at sea
It's going back a ways but I recall the DHC dash 8 (PW 120's turboprops) had an ETOPS AFM supplement for some south pacific/ aus/nz operators.
I doubt a piston engine would ever be ETOPS qualified.
I doubt a piston engine would ever be ETOPS qualified.
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From: Estonia
Wankel...
And how many piston engines are needed for long haul? Is 4+ needed (B-36 has 6, Hughes Hercules has 8, Saunders-Roe Princess has 10 and Dornier X has 12), or is 3 enough?
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From: Boldly going where no split infinitive has gone before..
Errrr.... And exactley which aircraft has flown equipped with Wankel engines???
As to the pistons you've quoted, none of them had more than four engines because of redundency. They had that many because they needed that much power from the best avaialble engines at the time.
A three-engined pison would no have any distance restrictions on it, provided it could maintain height on any one, but the engineering difficulties of odd numbers of engines has meant that these have been a rarity (Tri-lader and Drover- both modifications of existing twins,and the 1930's Fokker and Ford tris are the only ones that spring to mind).
As to the pistons you've quoted, none of them had more than four engines because of redundency. They had that many because they needed that much power from the best avaialble engines at the time.
A three-engined pison would no have any distance restrictions on it, provided it could maintain height on any one, but the engineering difficulties of odd numbers of engines has meant that these have been a rarity (Tri-lader and Drover- both modifications of existing twins,and the 1930's Fokker and Ford tris are the only ones that spring to mind).
Last edited by Wizofoz; 6th November 2006 at 09:28.
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From: flyover country USA
Wardair operated 727's YVR-HNL long before ETOPS. However in the early days of DC-10 & L1011 marketing, there was some reluctance to employ trijets for transoceanic routes -- some airlines thought their customers might not accept the idea.
There was never a regulatory problem, was there?
BTW - ETOPS applies only to twins - not to 3/4/5/6/8/10 engines!
There was never a regulatory problem, was there?
BTW - ETOPS applies only to twins - not to 3/4/5/6/8/10 engines!
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From: Boldly going where no split infinitive has gone before..
I do see your point.
"Unless authorised by the administrator"= ETOPS, which have been developed especially for twin engined, turbine powered aircraft.
If you want to fly a piston twin more than one hour from an airport the answer is usually no except for special authorisations such as ferry flights.
If you want to get authorisation for your three engined Piston or twin wankel aircraft, put together a case showing that the particular airframe/engine/operator combination provides equivelent safety. Difficult because very few of the former and none of the latter exist.
"Unless authorised by the administrator"= ETOPS, which have been developed especially for twin engined, turbine powered aircraft.
If you want to fly a piston twin more than one hour from an airport the answer is usually no except for special authorisations such as ferry flights.
If you want to get authorisation for your three engined Piston or twin wankel aircraft, put together a case showing that the particular airframe/engine/operator combination provides equivelent safety. Difficult because very few of the former and none of the latter exist.
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From: Estonia
I do see your point.
"Unless authorised by the administrator"= ETOPS, which have been developed especially for twin engined, turbine powered aircraft.
If you want to fly a piston twin more than one hour from an airport the answer is usually no except for special authorisations such as ferry flights.
"Unless authorised by the administrator"= ETOPS, which have been developed especially for twin engined, turbine powered aircraft.
If you want to fly a piston twin more than one hour from an airport the answer is usually no except for special authorisations such as ferry flights.
Is there any literal regulatory rule that even if a piston engine were to demonstrate IFSD statistic matching the ETOPS thresholds, it would be ineligible to ETOPS just because it is a piston engine?
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From: Boldly going where no split infinitive has gone before..
What about comparing a piston engine of 2006 with a turbine engine of 1966 or 1986?
As I said, ETOPs is basically an exemption from the rues under a particular set of guidelines. I suppose it is concievable that a theoretical piston could demonstrate the required reliability, in which case you could request that it be included or a new set of guidelines be set up. I doubt that any such engine exisits, however, and would be interested to know what operation you propose would need an ETOPs piston rather than a turbine?
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From: Estonia
As I said, ETOPs is basically an exemption from the rues under a particular set of guidelines. I suppose it is concievable that a theoretical piston could demonstrate the required reliability, in which case you could request that it be included or a new set of guidelines be set up. I doubt that any such engine exisits, however, and would be interested to know what operation you propose would need an ETOPs piston rather than a turbine?
Why are there still piston-engined propeller planes - why arenīt they all turboprops? And on land, while Mazda keeps producing Wankel cars, gas turbine cars do not appear popular.
