Water landings IRL?

[Rutabaga22]

In ksp I sometimes have to do water landings in ksp with my planes. In real life would a water landing with a plane be safe?

[kerbiloid]

No, but usually you have time to leave it.

[Vanamonde]

Your question has been moved to the real spaceflight sub since you're not asking about the game. 

But I don't understand your question since there are planes which were made to land safely on water 

and it has occasionally been done in emergency situations. 

So the answer is yes, unless you mean something else. 

[kerbiloid]

https://aerocorner.com/blog/do-airplanes-float-on-water/

[mikegarrison]

As @Vanamonde said, there are planes designed to land on water or land, planes designed ONLY to land on water, and planes designed to land on land that end up in the water ("ditching"). (There are also planes designed to land on boats, which is not quite the same thing.)

Ditching is still a certification requirement, but there were few or no fully successful ditchings of jet airliners until the Hudson incident.

[Piscator]

Spoiler

 

And then there are planes designed to land on land, but land on water anyway when its hibernating and can't defend itself.

 

 

 

[Nuke]

seeing as i live not to far from a float plane dock, id say that water landings are pretty routine. i really wish they would bring back large format sea planes. 

[mikegarrison]

48 minutes ago, Nuke said:

seeing as i live not to far from a float plane dock, id say that water landings are pretty routine. i really wish they would bring back large format sea planes. 

There is a very old saying about flying boats: they aren't very good boats, and they aren't all that good at flying either.

[Rutabaga22]

I meant Waterlanding with planes not meant for it.

 

[Vanamonde]

55 minutes ago, Rutabaga22 said:

I meant Waterlanding with planes not meant for it.

 

It's been done in emergencies, but the best case scenario is that the passengers and crew survive while the plane is a total loss. 

[mikegarrison]

2 minutes ago, Vanamonde said:

It's been done in emergencies, but the best case scenario is that the passengers and crew survive while the plane is a total loss. 

This is not quite the "best scenario".

This airplane was restored and is now sitting in the Udvar-Hazy gallery.

(It was a restored Boeing Model 307 Stratoliner. It was basically ready to be flown to the Udvar-Hazy when, during a test flight, it ran out of fuel. The pilots ditched the airplane right next to the shore. Unfortunately, it then required a bunch more restoration before it could finally be flown to the museum.)

(Personal note, I got a short tour inside that airplane while it was being restored. Restored the second time, IIRC. Then later I saw it again while I toured the Udvar-Hazy.)

[Pixophir]

On 7/7/2022 at 12:33 PM, Rutabaga22 said:

In ksp I sometimes have to do water landings in ksp with my planes. In real life would a water landing with a plane be safe?

It is the best chance to survive, e. g. in case of stalled engines or out of fuel, and when there is no surface in range to risk an emergency landing, but it would not be safe. Actually, as @mikegarrison said, many water landings go wrong. Slow flying aircraft have a much higher chance of success than fast jets with their high approach speeds, specifically short after take off when the plane is heavy.

Chances are best on flat water (lake, estuary, river mouth like the exceptional ditching on the Hudson). When ditching on the open ocean, one can try to "land" perpendicular to the travel of the swell in a valley.

Such a situation usually does not leave much time for decision making, witch raises the risk because of the stress put on the crew.

https://en.wikipedia.org/wiki/Water_landing#Passenger_airplane_water_ditchings

Edit: The respective flight manual may have some recommendations on how to set up the plane for ditching, but as said there is often simply no time. And afaik there is not enough data to support general recommendations.

Edited July 9, 2022 by Pixophir
Clarified some detail

[kerbiloid]

It's better to land, if possible. But it's not always possible.

The water drag still can crash, rotate, and/or overturn the plane, while on the ground you can slide.
Unlike the ground, it has waves, which are an effective replacement of the ground pits and heaps.
And once you had landed, you won't sink. Don't forget that divers don't pass to tens meter depth as quick as a plane sinks.

And it's easier to aim along the ground than along the water with its reflections and flash dance, and absence of stable details to estimate the altitude.

Edited July 9, 2022 by kerbiloid

[jimmymcgoochie]

For a plane built specifically to land on water, it’s possible but still risky as water, unlike a solid runway, tends to be uneven and produce a lot of drag which needs to be carefully countered to land safely. Seaplanes and flying boats also have the disadvantages that come from lugging around all that floatation-related stuff as well as design features intended to make taking off and landing easier but which will add drag and/or weight e.g. larger or angled wings to increase lift.

Landing on water is an ‘if all else fails’ option for most planes because it’s incredibly risky:

• Any plane with a fixed landing gear will almost certainly flip upside down on landing as the wheels hit the water and generate huge drag on the bottom of the plane, potentially killing the occupants with the deceleration and impact forces as well as whiplash that could break your neck;
• Planes as a rule are as light as possible, so their fuselages tend to be pretty fragile when hitting the ground or water at any kind of speed. A forced landing or ditching also subjects the structure to extreme loads in unusual directions which can cause it to break apart, which on water will make it sink;
• Unless you’re landing on a lake in calm weather, water tends to be uneven and constantly moving. Trying to land a plane in an emergency is hard enough without having to deal with waves that could snag a wingtip, an engine or the fuselage and drag the plane down in an unstable way (read: wing rips off, plane rolls over and ends up upside down);
• People inside a plane that has just ditched will understandably panic, but this can lead to them inflating life jackets inside the plane- if the plane is sinking and the door is below the water, they can’t get to it because the life jacket makes them float and now they’re trapped in a sinking plane;
• Jet fuel floats on water, so in the event of a fuel leak and fire after the crash any survivors in the water are in serious danger of being covered in burning fuel, whereas on land you can get uphill and away from the fire.
• Water is generally colder than human body temperature so even in otherwise warm conditions hypothermia is always a danger- and the colder the water is, the worse it will be. There’s a reason that most of the Titanic’s passengers in lifeboats survived whereas those who ended up in the water did not, and it’s not drowning.

Look up Ethiopian Airlines 961 to see exactly why ditching a plane in the water is A Bad Idea and only ever used as a last resort.

At least with a crash-landing on land, you don’t have to worry about the plane sinking afterwards. Passengers too injured to move or trapped in the wreckage have a chance to be rescued, the wreckage (and so the survivors) can be more easily located and there are a lot more land-based emergency response vehicles and personnel than there are sea-based as well.

[StrandedonEarth]

1 hour ago, jimmymcgoochie said:

Look up Ethiopian Airlines 961 to see exactly why ditching a plane in the water is A Bad Idea and only ever used as a last resort.

Not really a good data point as the pilot was fighting off a suicidal hijacker while trying to ditch. Just re-watched the video, and the wingtip was in the water for a few seconds and then the engine, and the pilot still nearly managed to level it off before the wingtip hit a coral reef, according to wiki.

Spoiler

 

https://en.wikipedia.org/wiki/Ethiopian_Airlines_Flight_961

But yeah, a water ditching is certainly a last resort. As for amphibious planes,  those are the best option short of a helicopter for landing in areas without a suitable runway or fairly flat field. Although some light aircraft can land on a sandbar in the right conditions...

Spoiler

 

 

 

18 hours ago, mikegarrison said:

There is a very old saying about flying boats: they aren't very good boats, and they aren't all that good at flying either.

The PBY Catalina begs to differ....

Spoiler

 

[SunlitZelkova]

On 7/8/2022 at 1:46 PM, mikegarrison said:

There is a very old saying about flying boats: they aren't very good boats, and they aren't all that good at flying either.

During WWII the Japanese built the A6M2-N and N1K1 floatplane fighters, both of which had great performance. Even the F1M observation floatplane was used to great effect as a fighter and bomber. These had no issues operating from atolls and small sounds in the Southeast Pacific.

Unlike the dinky OS2U, it’s Japanese counterpart, the E13A, flew quite a few combat missions or missions extremely close to combat, including flying at low altitude over the US fleet during an engagement at Guadalcanal to drop flares over them.

Like the above mentioned PBY, the H6K4 and H8K2 had stellar performance as patrol aircraft during the war. They also had no issues operating from their water bases.

I mention floatplanes as there is likely a misperception about their performance too.

[magnemoe]

I say its easier to survive an water landing in KSP than in RL as the crew models is much more sturdy than real airplane fuselages. 
You still need to specially design an plane to be able to land on water.
Yes an vtol plane could easy land and take off from water in KSP. In real life this would again be an bad idea unless plane was designed for it, getting the air intakes flooded for one and water damage to electronic.