While there are not as many turboprop types in production as there used to be in the past, aircraft like ATRs and Dash 8s are still quite popular among some airlines. In other cases, like for flights to short, unpaved runways, they are indispensable.
In spite of that, many passengers try to avoid flying on them whenever possible. Continue reading to learn what the differences between turboprops and jets are and to see whether you should be actively avoiding turboprops or not.
Spoiler alert: you don’t have to…
Turboprop vs. Jet Engines: What Are the Differences?
Obviously, the biggest difference between turboprop and jet aircraft – and the thing that all of the other differences arise from – is in the type of engine that the aircraft use.
The turboprop engine was first designed by György Jendrassik, a Hungarian mechanical engineer, who patented the idea in 1929. The first production aircraft to use turboprop engines was the Vickers Viscount which took off for the first time in 1948. Today, ATR 42, ATR 72, and DHC-8-Q400 are the most popular aircraft types using turboprop engines.
In a turboprop engine, energy generated by combusting fuel is turned into torque to spin a propeller attached to the front of the engine. That, in turn, provides the thrust necessary to move the aircraft forward. Because most of the energy is used for that, engine’s exhaust produces very little thrust.
A jet engine, on the other hand, directs the generated energy out of its exhaust which in turn provides the thrust to move an aircraft forward. When it comes to airliners, the majority of them uses turbofans – a subtype of jet engines that had a large fan at the front of the engine to increase airflow.
Turboprop vs. Jet Aircraft: What Are the Differences?
Now that you know the basic difference between a turboprop and a jet engine, let’s take a look what it means for aircraft using them.
Speed and Fuel Efficiency
Generally speaking, turboprop aircraft are slower than jet aircraft. In addition to that, turboprop engines generate less thrust than jet engines, and so they are more suitable for smaller aircraft.
While turboprop aircraft are efficient at low altitudes (i.e. where the air is denser) and low speeds, jet aircraft are more efficient at high altitudes (i.e. where the air is less dense) and high speeds.
Those are the main reasons why today, turboprop aircraft are used almost exclusively on short routes with relatively small capacity. In other words, they are mainly used on routes where the speed difference between a turboprop and a jet don’t amount to a considerable difference in travel time.
For example, a 250-mile flight from Vienna to Innsbruck might take 50 minutes on a DHC-8-Q400 as opposed to 40 minutes on a jet. However, accounting for the time spent taxiing, waiting for take-off, etc. (i.e. time that is the same regardless of the aircraft type), the difference in the actual travel time is negligible.
On the other hand, jet aircraft are generally more efficient on longer routes where cruise makes up a considerable portion of the total flight time. That allows for the efficiency lost at lower altitudes (during climb and descent) to be made up for during the high altitude cruise.
Acquisition and Maintenance Costs
With jets being more advanced than turboprops, it comes as no surprise that the former are more expensive to acquire than the latter when looking at aircraft of similar capacity.
As an example, let’s take a look at the ATR 72, one of the most popular turboprops in the market today, and CRJ-700, a regional jet of roughly the same size. While the turboprop ATR sells for about $25 million, the latter costs over $40 million.
It’s not only the acquisition cost that makes jets expensive, though. Being much more complex machines, they also require much more effort to maintain.
For example, maintenance costs for a small turboprop like Beech King Air or Piper Cheyenne are roughly $10,000 per year. On the other hand, a more complex jet like the Cessna CitationJet 2 can cost as much as $500,000 per year to maintain.
That’s in spite of the fact that in terms of fuel consumption, they are very similar.
Reliability and Safety
Because of the much easier accessibility of turboprops compared to jets – and their various non-transportation uses like skydiving – it is really difficult to fairly compare the safety of the two types of aircraft.
Statistically, turboprops might be a bit less safe (although the difference is negligible) since they operate shorter flights and thus spend more of their flight time in the most dangerous phases of flight – take-off and landing.
However, when used as airliners by fully qualified pilots, they are both jets and turboprops are extremely safe and the difference between them is not worth even looking at. Both of them are considerably safer than other means of transportation.
As already indicated to some extent above, the different characteristics of the two types of aircraft make them suitable for different types of routes.
Starting with the basics, turboprops are ideal for very short routes of a few hundred miles. That’s because in those cases, the slower speed doesn’t affect the total travel time including time spent on the ground too much. With those routes, the aircraft doesn’t need to climb to higher flight levels (above FL300 or 30,000 feet) either.
Jets, on the other hand, are perfect for routes that are at least seven or eight hundred miles. They are ideal for flights where the cruise portion is long enough to allow the aircraft to climb to higher altitudes like FL330 or FL350.
All that said, things are not always ideal. There are airlines using their turboprops on flights as much as 1,000 miles long and jets on flights as short as 150 or 200 miles.
Besides the above, there are also differences in the types of airports the two types can operate from. While most jets require relatively long paved runways, turboprops are more forgiving.
Because of their slower speed, they are able to take-off and land from shorter runways. Some of them are also able to use unpaved runways (Loganair’s flight to Barra landing on a beach being one of the most notable examples) as their engines can tolerate more debris than jets can.
Why Are Jets More Popular Among Passengers Than Turboprops?
Reading the above, you might come to the conclusion that turboprops are not that different from jets. Especially so when it comes to commercial flights operated under strict regulations. Yet, many people perceive flights on turboprops as something to avoid.
One of the reasons people prefer jets is because they perceive them to be faster. While that is true, it is also true that on the flights where a turboprop will be used, the difference in travel time will be negligible. How long you wait for your luggage at your destination will probably have a larger effect on your overall experience.
Another reason is safety. While statistically, commercial flights on both turboprops and jets are extremely safe, turboprops can be perceived as unsafe. That’s, I believe, largely because when there is an aircraft accident mentioned in media, it oftentimes is a prop aircraft.
Combine that with the fact that most people don’t recognize the differences between general and commercial aviation, between pistons and turboprops, and so on, and you can start to understand why turboprops don’t have as good of a reputation as jets.
In practice, the biggest reason to avoid turboprops should be the fact that they can be louder in the cabin than jets. Even then, however, the newer generation aircraft like the latest ATRs are relatively quiet – and the noise is nothing that cannot be managed on the short flights that these aircraft generally operate.
Both turboprops and jets are extremely safe when in airline operation. That said, there are some notable differences between them. To just one of them, turboprops perform at their best at low altitudes and speeds while jets are more efficient at high altitudes and speeds.
That’s also the reason why the former are better suited for short flights while the latter is better suited for longer flights. More precisely, jets are better suited for the flights where the cruise portion makes up a considerable part of the overall travel time.
Turboprops, on the other hand, are perfect for flights that are short enough for the slower speed not to matter. In other words, they are ideal for flights where a considerable part of the total travel time is spent on the ground.