Explain Weather to Me From a Pilot's POV

[KLB]

Some days I can fly through the stuff and only hit a little moderate turbulance while other days I come out the other end regretting my decision to go through it in the first place. As I gain more experience, I find myself less compelled to try a find a way through the weather that appears to be rough compared to just taking the deviation. Better safe than having my head hitting the ceiling and all the charts flying all over the cockpit.

If it looks real bad ahead, I stop requesting and start telling the controller what I'm going to do.

 

[derg]

And a question about that. Oftentimes I'll be the non-flying pilot where we need permission to deviate left or right for weather, but there's always some yahoo taking five minutes to check in ("HellLLoOOoOOO Boston CENNNAH! Airliner Twenny ONNNNNNNNNE Forty Two, with you, on deck, at Flight levellllllllllllllllllllllllllllllllllllllll twooooo three zerrah, looking for umm, yeah, looking for ride reports at 280, requestin' two nine oh, looking for airport advisories for...") where after a while, I'll just tell him "Turn where you gotta turn, I'll work it out with ATC when I can cut in".

I wonder is that kosher or should I just penetrate the weather in the meantime...

 

[boondr]

And a question about that. Oftentimes I'll be the non-flying pilot where we need permission to deviate left or right for weather, but there's always some yahoo taking five minutes to check in ("HellLLoOOoOOO Boston CENNNAH! Airliner Twenny ONNNNNNNNNE Forty Two, with you, on deck, at Flight levellllllllllllllllllllllllllllllllllllllll twooooo three zerrah, looking for umm, yeah, looking for ride reports at 280, requestin' two nine oh, looking for airport advisories for...") where after a while, I'll just tell him "Turn where you gotta turn, I'll work it out with ATC when I can cut in".

I wonder is that kosher or should I just penetrate the weather in the meantime...

Throw 7700 in the box and do what you have to, we'll get the picture. The reality of the situation is if the PIC truely believes safety is at risk it is an emergency and should be treated as such. Even if it is only short term flight safety should never take a backseat to efficiency or plans etc.

 

[derg]

Thanks!

It rarely involves a massive deviation, just about 10 degrees or so for a short period of time.

 

[Vector4Food]

Sidenote to all this...

Flew out of Toronto in a 737-700 couple days back we had to deviate around some thunder bumpers, well we hit some turbulence which lifted my fat ass outta my seat a few times just a bit, stuff moving around, I fly quite a bit and it was rather rougher than anything I've had before flying commercially.

Just out of curiosity and Atc related I asked the pilot after what he would have categorized that turbulence as, he said ohhh light turb maybe moderate chop at the worst.

Now I was sitting three rows from the back but the intensity was far more than light to me, just goes to show how bad severe must be to the pax in the back when a pilot reports it to me

 

[boondr]

Thanks!

It rarely involves a massive deviation, just about 10 degrees or so for a short period of time.

I never understood why pilots tend to shy away from the ultimate trump card, the emergency, there is nothing that says that you have to take that emergency to the ground immediately or already have a problem. IMO if ATC shuts you down by giving you no options other than going against instructions and you HAVE to deviate than it is an EMERGENCY, you need the priority so you take it. It actually covers everyone involved nobody will get in trouble(barring the 1 in million anti-big sky theory). So if some yodel is yammering away on the frequency and ATC can't approve your request, than by default, the situation is the same, declare, then two mins later(or however long) say problem solved no more emergency. That way when the "snitch patch" at the center goes off because your deviation caused a separation error, you're not trying to defend a "possible pilot deviation" by saying you had an emergency situation but didn't declare as such.

 

[derg]

I never understood why pilots tend to shy away from the ultimate trump card, the emergency, there is nothing that says that you have to take that emergency to the ground immediately or already have a problem. IMO if ATC shuts you down by giving you no options other than going against instructions and you HAVE to deviate than it is an EMERGENCY, you need the priority so you take it. It actually covers everyone involved nobody will get in trouble(barring the 1 in million anti-big sky theory). So if some yodel is yammering away on the frequency and ATC can't approve your request, than by default, the situation is the same, declare, then two mins later(or however long) say problem solved no more emergency. That way when the "snitch patch" at the center goes off because your deviation caused a separation error, your not trying to defend a "possible pilot deviation" by saying you had an emergency situation but didn't declare as such.

I think we're just taught from mere hatchlings that once you declare and exercise emergency authority, it's like declaring DEFCON 1 in the Cold War and the walls come tumbling down, the FAA kidnaps your children and crazed spider monkeys run amok in dear mother's herb garden so it's got to be one of those "I will most certainly DIE" situations.

 

[derg]

Just out of curiosity and Atc related I asked the pilot after what he would have categorized that turbulence as, he said ohhh light turb maybe moderate chop at the worst.

Now I was sitting three rows from the back but the intensity was far more than light to me, just goes to show how bad severe must be to the pax in the back when a pilot reports it to me

I think it's a combination of the fact that, depending on aircraft type, it can feel really like light chop in front, but in the back of the aircraft feel like armageddon. I think the Airbus's (airbuses? Airbii?) are like this.

Now the other double-whammy is the descriptions of light, moderate and severe turbulence.

Light:
Aircraft Reaction
Turbulence that momentarily causes slight, erratic changes in altitude and/or attitude (pitch, roll, yaw). Report as Light Turbulence;

or

Turbulence that causes slight, rapid and somewhat rhythmic bumpiness without appreciable changes in altitude or attitude. Report as Light Chop.

Reaction Inside Aircraft
Occupants may feel a slight strain against seat belts or shoulder straps. Unsecured objects may be displaced slightly. Food service may be conducted and little or no difficulty is encountered in walking.

Reporting Term Definition
Occasional-Less than 1/3 of the time.
Intermittent-1/3 to 2/3.
Continuous-More than 2/3.

For brevity:

Moderate
Aircraft Reaction:
Turbulence that is similar to Light Turbulence but of greater intensity. Changes in altitude and/or attitude occur but the aircraft remains in positive control at all times. It usually causes variations in indicated airspeed. Report as Moderate Turbulence; 1
or
Turbulence that is similar to Light Chop but of greater intensity. It causes rapid bumps or jolts without appreciable changes in aircraft altitude or attitude. Report as Moderate Chop.

Reaction Inside Aircraft:
Occupants feel definite strains against seat belts or shoulder straps. Unsecured objects are dislodged. Food service and walking are difficult.

Severe
Aircraft Reaction:
Turbulence that causes large, abrupt changes in altitude and/or attitude. It usually causes large variations in indicated airspeed. Aircraft may be momentarily out of control. Report as Severe Turbulence.

Reaction Inside Aircraft:
Occupants are forced violently against seat belts or shoulder straps. Unsecured objects are tossed about. Food Service and walking are impossible.

Ultimate
Turbulence in which the aircraft is violently tossed about and is practically impossible to control. It may cause structural damage. Report as Extreme Turbulence.

 

[Screaming_Emu]

I have no idea at all. I thought it had something to do with a CRJ being better equipped to fly through that weather than a MD88, which doesn't really make sense at all to me.

Its all up to the PIC. Ideally if I can avoid anything that is big and puffy I will. While mass of the airplane tends to play a role in how much turbulence is felt, a thunderstorm is a thunderstorm.

Equipment wise, the only other thing I can think of is radar. Not all radars are created equal. I know in the CRJ I've been told many times that people are deviating and my question was "around what?" as I tilt the radar up and down and paint only ground.

Thunderstorms are absolutely scary to go through. I've been scared twice since I started doing the 121 thing and they both involved getting a bit too personal with storms.

Small buildups are a different story. They might not appear on the radar yet, but you can still get knocked around pretty good when you go through them. If I know the flight attendant is still up and about I'll avoid them like the plague. One of my favorite things actually is when we're told we can deviate as needed. If there's a bunch of them I'll click off the autopilot and weave around them. If its smooth outside them I'll see if I can drag a wingtip through them, but just barely. But if we've told the flight attendant to sit down early and it isn't growing too rapidly, a couple seconds of bumps probably won't do any harm.

 

[Screaming_Emu]

It is possible that the dispatcher for the MD wasn't comfortable and gave his/her recommendations. Remember ATC is not the only set of eyes watching a commercial flight

I highly recommend a tour of Delta's Operation Center if you can get it. I don't see why they would deny it after you explain your reasoning. Also, see if they will let you sit with a dispatcher for a couple of hours besides the 25 cent tour.

While I appreciate that you're a dispatcher and trying to give that side of it, I don't know how realistic that is, at least at my company.

Don't get me wrong, they're a great group of people who work hard and are a fantastic resource. But in all honesty I think they're working entirely too many flights. While it does make my day when we get a message giving us a heads up about something like storms, it seems like everything my company does is reactive instead of proactive. There always seems to be a hole until you get there.

This isn't meant as a swipe at our dispatchers, but rather the way every company seems to be nowadays, they're trying to do too much with as few people as possible.

 

[dasleben]

Well said. If safety of flight is an issue do what you need to do but also consider there are other planes out there. Today for example I had a Bonanza request 15 right for wx, which in my view put him in the worst possible spot. I offered anything upto and including 180 left but not right(there were 5 jets at or descending through his alt in that area he wanted to go) but right although it had more painted then left was a shortcut. Remember if separation is an issue we HAVE to deny it initially because otherwise the error belongs to us. Do what you have to but remember there is more to it than us being lazy. The Bo stayed on course rather than go out of his way to the left with no problems.


*I think dasleben was on freq during this he can attest to the insanity that was my sector at the time.

Yeah, I was on frequency for that. I remember thinking "Why doesn't this guy just take something?" Seems like he just rolled over and accepted the idea of going right through it. :dunno:

 

[boondr]

Yeah, I was on frequency for that. I remember thinking "Why doesn't this guy just take something?" Seems like he just rolled over and accepted the idea of going right through it. :dunno:

In reality I think he wanted a shortcut. You were right in front and below him at 4 and I had jets above him at 6/7/9 flying right through his area. In fact the cell you didn't want to go through after I gave you to final was right where he wanted to go. I refused because 1) put him too close to everyone else 2) put him into the worst weather that nobody else would fly through. Funny how that 15 deg. right just skipped a few intermediate fixes on his route.