How many reserve planes are typically lying around in airlines? Not many. Airlines can't function like the Air Force and have numerous expensive jets lying around "just in case."
Still, aircraft breakdown and mishaps happen while political/weather/other factors may ground their aircraft. Airlines are also called on to perform rescue flights when a crisis breaks out (these aircraft need to be pulled form somewhere).
In these situations, airlines may need to call on another aircraft—but do they have reserve planes lying around?
There isn't much information about how many aircraft an airline keeps as spares. The number of available aircraft that can be called on (or pulled from other operations) is likely to be higher in the winter/low season periods. In the peak season, the airline may not have many "spare" aircraft at all.
In 2018, the blog From the Holocron wrote that US Airways (now emerged with American Airlines) stated it had around 13 planes in reserve.
"Since we operate a “different” schedule each day the number fluctuates a bit. Today for instance, we currently have 340 active lines of flying on the mainline operation. Here is what we have built into the schedule for spares: 13 spares total…. 2 737’s (covering 300s and 400s), 7 Airbus (covering 319/320/321), 2 B757 (covering 757/767), 1 A330 (covering A330-200 and 300) and 1 EMB 190." - US Airlines (reported by Crankyflier in 2012)
In fact, according to US Airlines' answer, the airline kept more or less one spare aircraft for each fleet type available.
|
US Airlines spare aircraft in 2012: |
Quantity: |
|---|---|
|
Boeing 737: |
2 |
|
Airbus A319/320/321: |
7 |
|
Boeing 757: |
2 |
|
Airbus A330: |
1 |
|
EMB 190: |
1 |
|
Total: |
13 |
Aircraft are phenomenally expensive to purchase, operate, and maintain (even if they are just sitting on the tarmac). No airline wants to have billions invested in aircraft sitting around, not generating income.
Therefore, airlines strive to keep their reserve fleets as low as possible and their fleets as active and productive as possible. Airlines operate on very tight profit margins, and keeping many reserve aircraft is not viable.
Airlines may have comparatively more widebody aircraft as "spares" as the pain of cancelation for those flights is typically higher.
Airlines keep certain spare parts for their aircraft on hand so that many can be quickly repaired. It should also be noted that aircraft maintenance is preventative maintenance—no airline wants to fix an aircraft after it breaks; they want to fix it before it breaks.
Russia is in a unique position as it is under international sanctions and is unable to purchase new aircraft to buy the spare parts it needs to maintain its existing Airbus and Boeing fleets (although it does possess considerable ability to keep them flying).
Russia is apparently particularly struggling to maintain the new CFM International LEAP engines found on its Airbus A320neo/A321neo fleets.
Reportedly, half of its Airbus neos are now grounded, and half of that number is not expected to fly again. The other half are grounded as "spares" of sorts to preserve their remaining engine life and be put back in service during the peak season when they are more needed.
Sometimes, an aircraft is forced to make an emergency landing in a remote airfield, leaving the passengers stranded. An example of that is in 2017 when Air France Flight 066 Airbus A380 suffered an engine blowout and had to make an emergency landing in a remote military airfield in Newfoundland. Air France had to send rescue aircraft to transport its stranded passengers.
That Air France incident shows another option airlines have - charter an aircraft. The Airbus A380 is the largest capacity passenger aircraft flying today, so no aircraft (short of another Airbus A380) has the capacity to pick up all of an A380's passengers (assuming it was full). The Air France A380 was carrying 520 people - 496 passengers and 24 crew).
The passengers on the A380 were not permitted to deplane, so time was of the essence to get them another ride. Air France dispatched two aircraft to pick up the passengers and crew - an Air France Boeing 777 and a chartered Boeing 737.
It is unclear which company Air France charted the Boeing 737 from.
Airlines may have some flexibility in having redundancy built into their flight operations. Airlines can increase the number of flights that run between hubs so that many flights have extra seats available.
If airplanes are not full, then it may be easier to accommodate passengers if a flight is canceled (or pull an aircraft from that route).
For example, if there are five flights a day from Los Angeles to NYC and one is canceled, the other flights may have enough slack to accommodate them. Alternatively, say a flight from Atlanta to Portland is canceled.
The airline may be able to move the passengers on other alternative routes (e.g., Atlanta to San Francisco connecting to Portland).
Example alternatives to having spare planes:
- Chartering an airplane
- Pulling an airplane from a route
- Loading passengers on alternative flights
The big issue here is that airlines don't want to be flying half-empty planes either. Still, there are benefits to having airplanes that are not completely full and having more than one possible way to route passengers to their end destinations.
Flexibility can be further enhanced by having codeshare agreements with other airlines. For example, one passenger had a Qatar Airlines flight from Cape Town, South Africa, to Yerevan, Armenia, via Qatar.
Qatar's Cape Town flight was canceled, so the passenger was transferred to a British Airways flight from Cape Town to London, where he changed to a Qatar flight to Doha and then to Yerevan.
