Go, no go questions

Bill

Bill

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OK, so here I am, 250 hour PP with IR, about 2 hrs actual, and we're going on a trip CHA->HXD and back for the weekend. Friday evening weather for the flight over looks good. Coming back, Sunday local forcast calls for mostly cloudy and 60% showers at Chat, good at Hilton Head. Commercial forcasts for areas in between show partly cloudy and 20-40% chance of showers.

120hr surface prog (1pm Sunday) shows a cold front right over CHA, and we'll be leaving HXD 3pm local, getting back to CHA 5pmish. So, we'll be crossing the cold front on the return flight.

Looking at the forcasts and surface prog, this appears to be a weak cold front, and I was just wondering the general wisdom of crossing cold fronts.

I know strong cold fronts can produce very severe weather, but what of the wisdom of crossing weak ones?
 

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Go for it!
I've crossed cold fronts with no clouds. This looks like a very good IFR flight. Without a lot of heat being generated you can probably be on top most of the way. There may be a cell or two to look our for though. Also, what is the temp differential between the two sides, and the moisture content on the front side?
 
N2212R said:
Also, what is the temp differential between the two sides, and the moisture content on the front side?
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Looking at temp forcasts at CHA, looks like a drop of about 10F after the cold front passage. As to moisture content front side, I'd have to research further.
 
I cross a cold front on the way from Albuquerque to 6Y9.

Let me tell you, it sucks. It was doable, picking my way more and more off course, until my original course was a pipedream, but it is definitely doable.

Good luck, and let us know how it goes if you do it. I'd like to hear that my experience wasn't typical.
 
SkyHog said:
I cross a cold front on the way from Albuquerque to 6Y9.

Let me tell you, it sucks. It was doable, picking my way more and more off course, until my original course was a pipedream, but it is definitely doable.

Good luck, and let us know how it goes if you do it. I'd like to hear that my experience wasn't typical.
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You weren't IR, Nick.
 
Bill,

As the time gets closer look carefully at the conditions (turb, ceilings, winds, etc) and make a final decision then. Is your wife going with you? Might want to add a significant safety factor for turbulance encounters in IMC since she is probably still a little nervious.
 
You will need to evaluate the front at the time you want to cross it. A few weeks ago I flew across a cold front VFR and it was no problem. The next day there was no way I would have crossed that same front even IFR.
 
Bill Jennings said:
OK, so here I am, 250 hour PP with IR, about 2 hrs actual, and we're going on a trip CHA->HXD and back for the weekend. Friday evening weather for the flight over looks good. Coming back, Sunday local forcast calls for mostly cloudy and 60% showers at Chat, good at Hilton Head. Commercial forcasts for areas in between show partly cloudy and 20-40% chance of showers.

120hr surface prog (1pm Sunday) shows a cold front right over CHA, and we'll be leaving HXD 3pm local, getting back to CHA 5pmish. So, we'll be crossing the cold front on the return flight.

Looking at the forcasts and surface prog, this appears to be a weak cold front, and I was just wondering the general wisdom of crossing cold fronts.

I know strong cold fronts can produce very severe weather, but what of the wisdom of crossing weak ones?
Click to expand...

So far the mission is a "Go". Keep an eye on the system as it developes.
 
Seems to me you have three areas of concern:

1) pilot
2) a/c
3) wx

Wx may drive 2 & 3.

Wx -

turbulence, ice/terminal wx destination and enroute and alternate

As a 250 hr pp with little actual you need to first honestly evaluate your abilities. What is your lowest acceptable actual Wx on the ground?

Next, I am guessing the a/c is a simple single so you won't have T storm detection/avoidance gear, nor will you have de-ice/anti-ice. So you have a very limited a/c to work with.

Ice - almost certainly not a problem on the East side of the front, but keep an eye on the west side. Just because there is an airmet for the possibility of ice doesn't mean there will be ice. Evaluate cloud types/ceiling and visibility. Can you stay in the warm air? If not can you stay out of the clouds? (I'm not suggesting VFR flight, but even IFR there are Wx conditions where you will accept time in the clouds but would rather not be in them).

Turbulence - As mentioned above, what is your and your passenger's levels of tolerance. A weak cold front is not likely to have turbulence sufficient to deter you, but think about it and have a solid reason for crossing it off the list (e.g. pireps are all for smooth air, forecast is for only light turbulence, etc.)

Mins. - Whatever your high mins are for yourself don't waiver. They are hard and fast and you must stick to them. I'd be concerned that if the front slows a bit you could get a situation with cold air over CHA, but alot of moisture still in the air and the fog could really mess things up. Same with en-route. You'll want to know what the terminal Wx is along the route so you know where to go if you decide not to press on or if there is a problem with ship or pax or pilot.

As Henning said, it is still wait and see - Sunday is a long ways away.

But above all be flexible, be prepared to leave early or late or even the next day. You should have NO plans for Monday that can't wait until Tuesday. It is Monday's plans that will get you killed on Sunday.

Sounds like a fun trip.

Fly safely.
 
Arnold said:
As a 250 hr pp with little actual you need to first honestly evaluate your abilities. What is your lowest acceptable actual Wx on the ground?
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I've been comfortable shooting ILS down to 400 actual, 200 hood, but that doesn't mean I'd be comfortable with 400 the whole way home.

Next, I am guessing the a/c is a simple single so you won't have T storm detection/avoidance gear, nor will you have de-ice/anti-ice. So you have a very limited a/c to work with.
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182 with XM nexrad and stormscope, so yes on weather detection, no on kice. Fully coupled AP that I've practiced ILS apps with to mins many times.

Ice - almost certainly not a problem on the East side of the front, but keep an eye on the west side. Just because there is an airmet for the possibility of ice doesn't mean there will be ice.
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I will absolutely be looking at pireps and air/sigmets for icing and turb potential.

Turbulence - As mentioned above, what is your and your passenger's levels of tolerance.
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I've had the crap kicked out of me, but I didn't enjoy it. Occasional mod is ok, severe, and I'm staying on the ground.

But above all be flexible, be prepared to leave early or late or even the next day. You should have NO plans for Monday that can't wait until Tuesday. It is Monday's plans that will get you killed on Sunday.
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That always does play into things, and I've always been ultra conservative. Someone else does have the plane booked for Monday for a trip to Destin, and we would like to be back at work.

If it looks at all like a return trip Sunday is questionable in any way, we'll likely just scrub and remain at home. Done that plenty of times before.
 
Yep, Cap'n Ron is right on. Backup plan should include, of course, as solid an idea of where to go/what to do if things get dicey as you can come up with before you even get into the cockpit.
 
Ron Levy said:
Get a good briefing, have a good back-up plan, and go for it.
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I always get a phone standard brief to back up and confirm what I've researched using internet weather sources. As for backups, I will work out good alternates along the return flight path.

If it looks OK, I'll go for it.
 
Bill Jennings said:
As for backups, I will work out good alternates along the return flight path.
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I think you misunderstand -- what I meant is to have a plan to deal with the situation if you can't safely return on Sunday, e.g., staying a couple more days, returning on the airlines, renting a car, etc. You don't want to have that "what will happen if I don't fly home today?" question wandering around in your head when you make that go/no-go decision on Sunday. If you've worked it all out ahead of time so there's no worries if you don't fly the plane home then, those "bad" thoughts won't interfere with a good flying decision.
 
Bill Jennings said:
OK, so here I am, 250 hour PP with IR, about 2 hrs actual, and we're going on a trip CHA->HXD and back for the weekend. Friday evening weather for the flight over looks good. Coming back, Sunday local forcast calls for mostly cloudy and 60% showers at Chat, good at Hilton Head. Commercial forcasts for areas in between show partly cloudy and 20-40% chance of showers.

120hr surface prog (1pm Sunday) shows a cold front right over CHA, and we'll be leaving HXD 3pm local, getting back to CHA 5pmish. So, we'll be crossing the cold front on the return flight.

Looking at the forcasts and surface prog, this appears to be a weak cold front, and I was just wondering the general wisdom of crossing cold fronts.

I know strong cold fronts can produce very severe weather, but what of the wisdom of crossing weak ones?
Click to expand...

There's a lot less energy in the sun this time of year (same as in late February) so the weather tends to be more widespread but less violent. The bigger issue may be ice, but this time of year it's common to have above freezing air at flyable altitudes so escape routes are more likely too.
 
IMHO it's way too early to make the call. Frankly, Friday evening is too early to make the call for a Sunday return. From the looks of things now I think you could go with a very high probability of return on Sunday. That's what you got your IR for. If things turn unexpectedly worse, an extra day in Hilton Head isn't the end of the world.
 
Hey! I'm at ground zero! :)

And I will attest the flying wx is either great or horrendous this time of year here...very rapid changes, often.
 
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Lance F said:
If things turn unexpectedly worse, an extra day in Hilton Head isn't the end of the world.
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Isn't that the truth! I have plenty of vacation stockpiled, so an extra day would be fine with me.
 
scottd said:
Bill,

What makes this a weak cold front?
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Obviously you'll tell me where I'm wrong, but here goes.

  1. The surface prog for Sunday shows light precip along the front where I will cross.
  2. The center of the low is far from where I will cross.
  3. The forcasts for multiple cities along my route show predictions of 40-60% chance of light rain showers. None of the forcasts are predicting TS.
  4. All of the forcasts along the route are predicting light winds, 5kts or less.
So, adding it all up, it looks like this cold front is not going to be a strong one that will be generating convective weather. It could all change, but that is what I'm going by.

Now, what is the professional analysis of this front?
 
Ron Levy said:
I think you misunderstand -- what I meant is to have a plan to deal with the situation if you can't safely return on Sunday, e.g., staying a couple more days,
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I have plenty of vacation on the books, and as Lance F said below, and extra day on Hilton Head is always nice.
 
Bill Jennings said:
Isn't that the truth! I have plenty of vacation stockpiled, so an extra day would be fine with me.
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There you go, no worries then. Oh BTW, another thing to add to the analysis is the distance between isobars. less distance, stronger winds and all the fun things that go along with. You did pretty good though.
 
Bill Jennings said:
Obviously you'll tell me where I'm wrong, but here goes.
  1. The surface prog for Sunday shows light precip along the front where I will cross.
  2. The center of the low is far from where I will cross.
  3. The forcasts for multiple cities along my route show predictions of 40-60% chance of light rain showers. None of the forcasts are predicting TS.
  4. All of the forcasts along the route are predicting light winds, 5kts or less.
So, adding it all up, it looks like this cold front is not going to be a strong one that will be generating convective weather. It could all change, but that is what I'm going by.

Now, what is the professional analysis of this front?
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Further, I've looked at the progression of the front as predicted by the progs, and specifically the high preceding the front.

Late Saturday, the high will be at the WV/MD/PA border area, and will be off the coast of DE by the time I will be departing. If the high were to go through below Chattanooga, and go off the coast in NC/SC/FL, then I'd be very concerned as that high would be pumping lots of gulf moisture (and warmth) up into the southeast. That would definately indicate a much higher chance of severe weather.
 
Bill Jennings said:
I've been comfortable shooting ILS down to 400 actual, 200 hood, but that doesn't mean I'd be comfortable with 400 the whole way home. 182 with XM nexrad and stormscope, so yes on weather detection, no on kice. Fully coupled AP that I've practiced ILS apps with to mins many times.
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When single pilot IFR, knowing and using an auto-pilot can make things a LOT more comfortable. My only question (and only you can honestly answer it) is: if you're flying home from Hilton Head with your wife and the ceilings at CHA are at 400', and the autopilot craps out, are you still comfortable hand-flying the approach, or are you autopilot dependent?
 
Troy Whistman said:
if you're flying home from Hilton Head with your wife and the ceilings at CHA are at 400', and the autopilot craps out, are you still comfortable hand-flying the approach, or are you autopilot dependent?
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I go out in the 172 and shoot 2-3 hand approaches almost weekly. I usually get 8-10 in per month.
 
Today's prog now shows the front going through as a dry front in the area concernng my flight, and the commercial surface forcasts have now downgraded the rain chances to 20-30% along the route of flight.

That is good.

But, it now shows the high preceding the front tracking along the northern TN and NC borders and out to sea. This is not so good, as the backside of the high could kick gulf moisture and energy into the SE prior to the arrival of the front.

Again, further watching is necessary. This is quite fun and informative even if we decide not to go on the trip.
 
Henning said:
There you go, no worries then. Oh BTW, another thing to add to the analysis is the distance between isobars. less distance, stronger winds and all the fun things that go along with. You did pretty good though.
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And something I forgot about on my trip back from NC....If you get strong winds and are crossing the mountains there can be some mountain wave. When I saw the lensticulars it all came back to me. A diversion and replan sent us on a safer route.
 
smigaldi said:
And something I forgot about on my trip back from NC....If you get strong winds and are crossing the mountains there can be some mountain wave. When I saw the lensticulars it all came back to me. A diversion and replan sent us on a safer route.
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BTDT, don't care to again. Our present flight path takes us over one mountain of ~4000ft. If there is an airmet tango, I'll modify the route to bring us back south of the mountain.
 
jdwatson said:
Mount Mitchell ?
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No, actually the last large hill to the south in the north GA mountains. Just NW of Dahlonega, GA. I can route us to NELLO and avoid if necessary.
 
Doesn't everything north of ATL below 10,000' have to go thru NELLO? :goofy:

Bill Jennings said:
... I can route us to NELLO and avoid if necessary.
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ATC here uses NELLO for routes leaving Atlanta. I can't get it coming back even if I want it.
 
Lance F said:
ATC here uses NELLO for routes leaving Atlanta. I can't get it coming back even if I want it.
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Hmmm, I've gotten it every time I've requested when coming back from the coast to CHA. Maybe becasue ATC knows we use it to duck in south of the mountains?
 
Steve said:
Doesn't everything north of ATL below 10,000' have to go thru NELLO? :goofy:
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It can get busy there, seven airways intersect at NELLO.
 
The decision has been made.

1.) The Chief Executive is uncomfortable with 30% chance of showers on the return flight.
2.) Her boss dropped a Monday 9am sales web meeting on her this morning. She is the sales/marketing manager and must be at the meeting.

So, uneasy passenger + Monday deadlines = no-go.

I thank you all for participating in this thread, it was fun and informative!

*sigh*
 
Bill Jennings said:
The decision has been made.

1.) The Chief Executive is uncomfortable with 30% chance of showers on the return flight.
2.) Her boss dropped a Monday 9am sales web meeting on her this morning. She is the sales/marketing manager and must be at the meeting.

So, uneasy passenger + Monday deadlines = no-go.

I thank you all for participating in this thread, it was fun and informative!

*sigh*
Click to expand...

You *could* always send her home on Greyhound.....
 
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