On sectors up to 500nm a turboprop carbon emissions per seat kilometre is around 40% less than a regional jet and yet most airlines prefer jets even for relatively short, low load sectors?
At some point the turbofans become more efficient due to higher payload and long haul efficiency factors, but low cost sectors would save a ton of carbon if they operated turboprops – ideally hybrid or with bio fuels.
RobertL18C wrote:
On sectors up to 500nm a turboprop carbon emissions per seat kilometre is around 40% less than a regional jet
I don’t think this is accurate. Compare number of seats, fuel burn per hour and time.
If a jet burns 2T/h and a TP burns 1.5T/h, the difference should be more like 15-20% (TP takes longer).
Yes, small turboprops for short sectors (less than 200NM) use only very little fuel (I recall a 50 seat Dash 8 burning around 350kg trip for a 90NM leg, sometimed as low as 280kg, but it was sloooow).
The 76 Seat Dash 8 was 100knots quicker (360 TAS) but used much more fuel.
Turboprops are also more expensive to maintain (more moving parts like prop/reduction gear etc..).
No matter which plane, these short sectors are not profitable anyway.
Apart from PSO routes or monopolies (Wideroe, Dash 8, Norway) the airlines are getting rid of turboprops, and they wouldn’t do it if it made sense to operate them.
With the razor thin margins the airlines operate on, everything is down to unit cost and economies of scale.
The trend is bigger planes (2 pilots/200 pax vs 2 pilots/50pax).
While a jet might only be a few minutes quicker on short flights in the long run they offer more utilization (legs per day), less time and usually lower unit costs due to bigger size.
Snoopy wrote:
Apart from PSO routes or monopolies (Wideroe, Dash 8, Norway) the airlines are getting rid of turboprops, and they wouldn’t do it if it made sense to operate them.
HOP (Air France) is indeed turning to ERJ instead of ATRs. I have been told it is mainly because when TP are to go over FL200, it starts to cost more in time and fuel. And also it is FIKI, ATR is known have trouble with medium icing…
Austrian is getting rid of all Dash 8.
The efficiency claim is partly manufacturer based (ATR), and research papers.
In theory the turboprop, and the turbofan, will achieve lowest SFC at high operating altitudes, eg F250 for the typical regional turboprop.
Where the turboprop suffers is the trade off between higher altitudes and headwinds, and the European CAS structure. In the USA typical SOP is F180 in headwinds and F250 with tailwinds, but in Europe going below F240 ends up with lots of vectoring. The trade off is less critical at Mach.75 compared to M.45.
If there is a 40% reduction in emissions per seat kilometre it’s odd that airliners switch. Some might argue BMI might have survived if they operated turboprops.
It is not only money and efficiency, it is also passenger appreciation. In the eyes of the wide public, turboprops are on one level with a JU52 and quite a few have heard one of those has crashed… but seriously, a lot of passengers do not like propellers, they feel unsafe on prop airplanes and will, given the choice, fly with an airline which uses jets (unless it’s cheaper…..)
On the portal I use to book work travel, there’s the following option, which shows how much of a dislike some people seem to have for propellers.
Mooney_Driver wrote:
but seriously, a lot of passengers do not like propellers, they feel unsafe on prop airplanes and will, given the choice, fly with an airline which uses jets (unless it’s cheaper…..)
I’ve heard that, too, but I’ve never understood the rationale behind the dislike.
Noe wrote:
shows how much of a dislike some people seem to have for propellers.
haha that is new to me, I guess SR22 is then excluded 
I can tick Boeing vs Airbus or Virgin vs UA but nothing about TPs
Airborne_Again wrote:
understood the rationale behind the dislike.
Most likely high wings, sitting on wing is far more natural
Ibra wrote:
Boeing vs Airbus
Seriously?
