carrier true winds

[kornic]

Please, I need some points of view for an interesting naval aviator bar chat that I had last week.
In fixed wing carrier operations, the ship always turns into the wind so that we get as much relative wind as we can. In this situation, most of the time the carrier turns into true wind. But what if the ship manages to create enough relative wind but having true wind from behind? Is it safe? Airplanes takeoff into the wind ashore to minimize rolling distance. But in an aircraft carrier would it make any difference taking off with 10 kts relative wind from the nose with 5 kt tailwind than taking off with 10 kts relative nose wind with 5 kts true nose wind?
As simple as it is, it has generated brainstorming among many pilots.
Any suggestions??
Thanks

 

[jg5343]

I always wondered about that too since a carrier can do 30 knots. What if it is mission critical to contiue on course yet still have to launch AC? as long as the relative winds are positive it shouldn't matter right? Can't wait to hear some feedback on this one.

 

[squeeze]

carriers typically steam to maintain ~25kts over the angle (11 degrees off BRC) during flight ops. if there's enough natural wind, all they need to make is a few knots to maintain manuevering speed. sorry, but i didnt really follow the true-relative question you're asking, but maybe i answered it.

 

[smittyrunr]

I think I understand what you're asking, and I'll explain it best I can.. they will do sometimes what is called a 'downwind recovery' where the carrier is moving the same direction as the wind, but is creating the requisite amount of relative wind over the deck. This does happen, although its not the preferred method of doing things. Makes life more difficult for the pilot because your normal corrections in the pattern aren't quite what you expect but not really a big deal. This situation really doesn't matter for take off, the landing is where it gets tricky because the pilot has a tailwind immediately upon turning final, the air becomes disturbed in the groove (this is the infamous 'burble'), and then as you cross the deck all of the sudden you have a ton of headwind and you are probably underpowered = LSO not happy. It's the change in the wind as you are trying to land and the disturbance caused by the interaction of true wind and natrual wind over the deck that makes things difficult. But not impossible.
Make sense? Maybe, but maybe I didn't answer what you were asking.

 

[Jolly Roger]

I have read an account of Cat shots from with little relative wind and anchored in the bay. In Feet Wet by retired Admiral Gillcrist he talks about launching the entire air group off the Saratoga with little relative wind and anchored in the bay of Piraeus, Italy.

Of course the aircraft had very basic fuel loads, but it is still impressive that they did that.

 

[wink]

smitty has it right. It wasn't so unusual for VS and VAW guys either. In my day anyway, the VS guys were at the top of the stack with the E-2 the only one above. By the time the S-3s recovered the ship would sometimes already be turning back on course. I have recovered several times with the ship in a turn, let alone with the ship making wind while running downwind. It may not be the ideal situation, especially recovering in a turn, but I don't ever recall any of my pilots boltering any more during those types of recoveries. The VS and VAW guys got abused like that all the time because their aircraft could handle those situations and the pilots were up to it. I have also known guys in other VS squadrons to launch at anchor. I never saw it though.

 

[VarmintShooter]

... landing is where it gets tricky because the pilot has a tailwind immediately upon turning final, the air becomes disturbed in the groove (this is the infamous 'burble'), and then as you cross the deck all of the sudden you have a ton of headwind and you are probably underpowered ...

I don't get it ... how is there suddenly a headwind? The ship is moving, so if you are standing on the ship you feel a wind, but if you aren't on the ship (ie. in the air) how does the wind suddenly change.

I guess the ship could block some of the wind, or it could create wind (by putting big a$$ fans on the flight deck), but other than that the ship's movement just creates a relative wind felt only if you are standing on the deck, not in the air recovering ... right?

I'm not really trying to contradict you guys (I've never landed on a carrier), just trying to figure out how the wind direction changes without the wind direction changing.

:icon_mi_1

 

[wink]

The aircraft flys an angle of attack, essentially an indicated airspeed for most air farce and civ types. It is, of course, a constant speed on the ball (if it isn't the LSO will not hesitate to debrief you on it). If the wind is out of the north at 10 knots and the ship's BRC is 180 and her speed is 20 knots you should have 10 knots over the deck. The aircraft's ground speed is 10 knots more then indicated relative to the sea but as you cross the round down the aircraft "ground speed", relative the deck, instantly becomes 10 knots less then indicated. Of course this unusual perception is relative the ship only and takes place in just a second or two before traping and I never noticed, but I wasn't driving. I think the biggest challenge is as smitty said, time in the groove and how the wind effects the burble. Slower planes like the E-2/C-2 and S-3 generally are effected by the burble more then the quick ones like the bugs. In a turn the island can block some of the wind briefly and that is noticable.

 

[VarmintShooter]

The aircraft flys an angle of attack, essential an indicated airspeed for most air farce and civ types. It is, of course, a constant speed on the ball (if it isn't the LSO will not hesitate to debrief you on it). If the wind is out of the north at 10 knots and the ship's BRC is 180 and her speed is 20 knots you should have 10 knots over the deck. The aircraft's ground speed is 10 knots more then indicated relative to the sea but as you cross the round down the aircraft "ground speed", relative the deck, instantly becomes 10 knots less then indicated. Of course this unusual perception is relative the ship only and takes place in just a second or two before traping and I never noticed, but I wasn't driving. I think the biggest challenge is as smitty said, time in the groove and how the wind effects the burble. Slower planes like the E-2/C-2 and S-3 generally are effected by the burble more then the quick ones like the bugs. In a turn the island can block some of the wind briefly and that is noticable.

Ouch ... my head hurts. I think I get it though.

Thanks.

 

[Eagle32]

VShooter,

And they (tailhookers) think they are cool, try a boost-out two-engine no flapper with a RCR of 12 and a 15 kt crosswind, yeah, now that gets the ladies.
We've got a Hoover driver in the squadron now, he can't flare, HA HA!

VP, yeah, we're dorks.

 

[bunk22]

There is also a minimum headwind componet required for all aircraft to land. Its been a while since my LSO days so I don't remember all of them but I do know the COD needs 25 knots, down the angle, stbd, or port. That's the highest of all carrier players and due to our slow on speed, we need a bit higher wind over the deck in case we lose an engine. It helps with our single engine controllability. With that being said, I've landed with the ship in a turn but they supposedly had the correct amount of headwind??

 

[wink]

but they supposedly had the correct amount of headwind??

You were an LSO and you believe that??!!!

You know I never thought about the Vmc thing on the ball. It was never an issue with the S-3 and I doubt it was with any of the other multi engine jets. I did talk with a Marine OV-10D guy extenisvely about CV trials with the Bronco. Vmc was a big problem for them since they had to be so slow to stop in a deck roll. Behind the power curve and below Vmc. After a successful landing you were rewarded with a deck run take off below Vmc. Not a recipe for ordinary operations.

 

[bunk22]

You were an LSO and you believe that??!!!

Nope, thus my question marks. That's all I've got though, trust in paddles to at least keep me off the back end of the boat. I remember one night, trying to get aboard the Connie with 5 wave-off's in a row. As I recall, they were trying to get that wind thing taken care of. It was a hazy night that became frighteningly worse after each wave-off. I don't believe it was the wind factor but they did what they had to do to keep me safe I suppose. Very glad to be back to day only boat ops