Hypothetical scenario...

cowman

cowman

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Cowman
You're a non-instrument rated pilot on a 3 hour VFR flight with 1 hour remaining. When you left and what was forecast along your route was few clouds at 3000-4500'. Seeing as how there were only a few poofy clouds, you opted for a cruise altitude of 7500'.

Now, with 1 hour remaining you observe that the few clouds below are starting to look more like scattered than "few". There are still certainly plenty of gaps to get down through but the cloud cover seems to be getting thicker rather than thinner.

You have ADS-B weather available and check your destination- METARS report says sky clear but you note the report is 45 minutes old. You tune in a weather station about 20nm ahead and it reports "scattered 3000".

What do you do now?

No right answer, this has never happened to me.... but I can easily see it happening. Curious what others would do.
 
Find a hole and descend. If I can't get down, I would call ATC
 
cowman said:
You're a non-instrument rated pilot on a 3 hour VFR flight with 1 hour remaining. When you left and what was forecast along your route was few clouds at 3000-4500'. Seeing as how there were only a few poofy clouds, you opted for a cruise altitude of 7500'.

Now, with 1 hour remaining you observe that the few clouds below are starting to look more like scattered than "few". There are still certainly plenty of gaps to get down through but the cloud cover seems to be getting thicker rather than thinner.

You have ADS-B weather available and check your destination- METARS report says sky clear but you note the report is 45 minutes old. You tune in a weather station about 20nm ahead and it reports "scattered 3000".

What do you do now?

No right answer, this has never happened to me.... but I can easily see it happening. Curious what others would do.
Click to expand...

1. If on FF, ATC will generally ask intentions if your destination is going IMC.
2. FSS will give you "the big picture" of closest VFR if your destination closes in on you. If scattered only, decision is where are the bases and do I want to ride the last hour under-neath in turbulence.
3. Hopefully you planned well with a generous fuel reserve.
 
Find a hole. And if you can't find one, make one for the next guy coming along behind you.
 
Going downhill to what was forecast...probably descend to 2500 when the scattered becomes obvious enroute and remain VFR below the scattered and take the bumps for the last hour...I have no problem flying over the top and have had this same scenario several times...and you only have to be let down once to come to this conclusion and I am IFR rated but always out of practice and if I wanted to be IFR I would have filed that way.
 
get the instrument rating...

otherwise ya gotta watch the clouds below and descend when necessary to remain VFR to the destination - no big deal

If you're on FF just tell'em you're descending to maintain VFR and if they say they will lose you then cancel radar service.
 
What's the terrain between me and the 030 at the destination?
 
Hmm I may have made this too easy but terrain is 700-1000'.

I might throw out what if it went down to scattered 2000'(this would be my personal minimum assuming good visibility)?
 
Pull back on the stick, while reducing throttle to idle, punch in a big right rudder and hold it for oh - about 5500'. When the altimeter reads ~ 2000' let go of rudder, release back pressure, and allow the speed to build a bit, then slow back pressure on course to level flight. Push the throttle back in and resume normal nav.
 
cowman said:
Hmm I may have made this too easy but terrain is 700-1000'.

I might throw out what if it went down to scattered 2000'(this would be my personal minimum assuming good visibility)?
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Clouds are AGL. You have about 1,300 feet of wiggle room with cloud and terrain clearance if the layer is at 3,000 feet. What airspace are you in down there? G gives you laxer cloud clearance requirements.
 
It happened to me taking my wife to Memphis for our anniversary. We stopped about half way to let the unforcast rainstorms go through but after I took off I couldn't get above 1500 for most fo the way there. The controllers were great even though they had a bunch of FEDEX aircraft lined up. We got around Memphis and into DeWitt Spain just as it was clearing so we were able to climb and avoid the antenna farm.
 
Being vfr you also might be pretty busy dodging SUA's and Class D depending on where you're going.
 
Sac Arrow said:
Clouds are AGL. You have about 1,300 feet of wiggle room with cloud and terrain clearance if the layer is at 3,000 feet. What airspace are you in down there? G gives you laxer cloud clearance requirements.
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Well I suppose it depends on what terrain you're over at that moment but 2500'MSL would put you in E, 2000MSL would put you in G pretty reliably.

If I had to go that low I'd want to find some assurance I'd be able to maintain that altitude or higher all the way in.... also around here I'd be looking at my sectional pretty closely for towers if I dropped down that low.
 
If you don't get below the cloud deck while you can do it VFR, this is a perfect set up for a low-fuel, stuck-on-top scenario.

Don't be that NTSB report.
 
cowman said:
I'd be looking at my sectional pretty closely for towers if I dropped down that low.
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I'd be looking pretty closely at my sectional for where I'm going to land when the weather continues it's downhill trend.
 
Chip Sylverne said:
Being vfr you also might be pretty busy dodging SUA's and Class D depending on where you're going.
Click to expand...

Flight Following eliminates those considerations unless they turn you loose due to workload....rare, but not impossible.

Bob Gardner
 
bobmrg said:
Flight Following eliminates those considerations unless they turn you loose due to workload....rare, but not impossible.

Bob Gardner
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It does happen. For me, about once a year for workload. Workload goes up when the weather sucks.

Center can also turn you loose because they lose radio contact. At low altitude, it really doesn't have to be remote at all. I've lost contact with NorCal flying through the Carquinez Strait (near Vallejo, CA) at 2000.

Closer to your neck of the woods, Seattle Center has no coverage north of KKLS below 5000.
 
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I would probably not immediately descend for scattered clouds. I'd just keep an eye on it and if it builds to the point that the holes themselves become scattered, I'd get down pronto.
 
I'm very conservative when it comes to something like that. I'd be getting below the clouds.
 
Scattered is 50% or less cloud cover. There is conservative, then there is overly conservative. Getting down a few thousand feet in 50% clear sky (or even 25%) should not present a problem.

To be clear, this is what we are talking about:

bhill%20trip%20111.jpg
 
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Call Flight Service or Flight watch and get the current weather from them at your destination. Whatever you do, don't get stuck on top with low fuel. If you don't have extra fuel, consider descending while you still can. Mark the spot of possible descent with a waypoint in your GPS so you can come back to it if you decide to stay on top.
 
bullwinkle said:
Scattered is 50% or less cloud cover. There is conservative, then there is overly conservative. Getting down a few thousand feet in 50% clear sky (or even 25%) should not present a problem.

To be clear, this is what we are talking about:

bhill%20trip%20111.jpg
Click to expand...
Big Sky Country? :D
 
bullwinkle said:
Scattered is 50% or less cloud cover. There is conservative, then there is overly conservative. Getting down a few thousand feet in 50% clear sky (or even 25%) should not present a problem.

To be clear, this is what we are talking about:
Click to expand...

If it's not a problem, then why did you personally descend so low! I mean, look at you... barely clearing the grass! :D
 
BTDT a number of times.

Early in my flying career, back when I was young, in this situation I would bump along the final hour(s) under the layer and after I land I would look up and realize that perspective is everything. I used to take the bumpy low road when the high road was just fine.

These days I'm more prone to fly above the layer and it works out mostly due to having XM weather and carrying 7 hours of fuel.
 
One situation I as flying above the clouds but looked ahead and it looked like the gap was narrowing, so I got down below them but the bases kept getting lower. I just turned around, wasn't a requirement to be at my destination anways. Glad I did, checked the weather once I landed, my destination (that was reporting scattered) was now reading overcast! Probably wouldn't have been able to get down VFR.
 
bobmrg said:
Flight Following eliminates those considerations unless they turn you loose due to workload....rare, but not impossible.

Bob Gardner
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Probably a result of flying outside the SFRA, but I think of FF as a supplement, not a substitute.
 
I agree with Bullwinkle, personally. If it's just scattered, then keep an eye on it and look out ahead for worsening conditions. If you're well above the tops you have a good view of what's up ahead. If/when the tops start to get closer together or you can see a broken layer coming, get down.

One of the first winter trips I made after getting my IR I let myself get beat up over 150 nm under a solid overcast, even though the layer was thin and my destination was clear, because I was afraid my destination would close up and I'd have to come down through the layer and land with some ice (FIP said 25-50% chance of trace to light). It didn't close up, when it was time to leave I departed in the clear and flew most of the way back VFR over a scattered layer and well into the point where it became broken, all in the nice smooth air on top. I was several thousand feet above the tops and when I could no longer see holes up ahead, I descended through a good-sized hole and endured the bumpy ride the rest of the way.

YMMV as always -- for a VFR only pilot the calculus might be different.
 
cowman said:
You're a non-instrument rated pilot on a 3 hour VFR flight with 1 hour remaining. When you left and what was forecast along your route was few clouds at 3000-4500'. Seeing as how there were only a few poofy clouds, you opted for a cruise altitude of 7500'.

Now, with 1 hour remaining you observe that the few clouds below are starting to look more like scattered than "few". There are still certainly plenty of gaps to get down through but the cloud cover seems to be getting thicker rather than thinner.

You have ADS-B weather available and check your destination- METARS report says sky clear but you note the report is 45 minutes old. You tune in a weather station about 20nm ahead and it reports "scattered 3000".

What do you do now?

No right answer, this has never happened to me.... but I can easily see it happening. Curious what others would do.
Click to expand...

Considering that I don't fool with dipsticks, if it's a short trip I'm carrying 3hrs fuel. For this trip I would be full fuel, which is 5hrs my only other fuel planning alternative. My personal mins are 4hrs flight time on 5hrs fuel. So, given the OP's scenario, I have plenty of gas if the cloud decks would close in on my destination for a turnaround to known VFR.

Secondly, Bob Gardner mentioned Flight Following, I use it (although I toyed with the idea of not doing so on my last Long XC). I can also query FSS if I'm in doubt about what I see on my on-board equipment and if they are consistent then I consider that +1 for my decision making.

To answer the question, I'd continue ahead. Seems to me that clouds without frontal systems or convective activity build slowly. I've got time to get the information I need, which needs to be more granular than a SCT report on ADS-B would provide. If it goes to BRKN, then I have to consider that I missed something in my planning and I'd go back to FSS and if necessary land and reassess.
 
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Sorry, I have to ask this but I'm not cognizant.

If you are tootling along on top VFR(yes, technically over the top) and things start to fill in below, and you think your destination will be IMC, what is flight following/VFR advisories going to do for you? I presume they can call FSS and get weather/forecast at the destination, but isn't that the pilots job? If you are not on FF, and you see the clouds becoming broken, is FF going to do something for you about that? Recommend a different vector(presuming you are direct destination)? Recommend you descend, recommend you remain VFR, give you a clearance to descend through the layer while VFR(seems illegal to me)? Aside from advising you on conflicts, what is FF responsibility? Declare an emergency for you? I just don't use them often enough to know this stuff.
 
docmirror said:
Sorry, I have to ask this but I'm not cognizant.

If you are tootling along on top VFR(yes, technically over the top) and things start to fill in below, and you think your destination will be IMC, what is flight following/VFR advisories going to do for you? I presume they can call FSS and get weather/forecast at the destination, but isn't that the pilots job? If you are not on FF, and you see the clouds becoming broken, is FF going to do something for you about that? Recommend a different vector(presuming you are direct destination)? Recommend you descend, recommend you remain VFR, give you a clearance to descend through the layer while VFR(seems illegal to me)? Aside from advising you on conflicts, what is FF responsibility? Declare an emergency for you? I just don't use them often enough to know this stuff.
Click to expand...

They may advise you ahead of time, but it is the pilots responsibility.
 
docmirror said:
They are going to advise you of what? It's getting cloudy? Your destination may be IMC?
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You're right Doc.

I don't often fly at these altitudes, but I did recently fly my XC back home at 7,500 and at that altitude on a CAVU day, I could make out my destination at 42 miles - could have been further if I was actively scanning for it prior to then, but that's when I could make out the river and then know to look for the airport. GPS told me that it was at 42 miles. So my point is that likely they wouldn't tell you much more than Mark-1 I-Ball could.

Bob?
 
BTDT. I check airports ahead to see conditions, i.e. does it become overcast or thin out. I can usually find someone who's updated. If it gets bad I either find a hole or do a 180 and find a hole. If not, I push on.

Truth be told about the only time I go on top is to get past rocks, which make weather and eat airplanes. It is often clear on one side and overcast in the mountains.
 
Part of the OP stipulates that the wx is already worse than forecast. You need to pay attention to that part, as once it starts going downhill, it often goes downhill pretty fast. It depends on the part of the country too. If you're in a coastal area, coastal stratus clouds filling in faster than forecast usually results in an IMC situation fairly rapidly. The other item to watch along the route is the temp/dewpoint spread trends, as that will add to the picture of how fast the situation could turn IMC.
 
docmirror said:
Sorry, I have to ask this but I'm not cognizant.

If you are tootling along on top VFR(yes, technically over the top) and things start to fill in below, and you think your destination will be IMC, what is flight following/VFR advisories going to do for you?
Click to expand...

docmirror said:
They are going to advise you of what? It's getting cloudy? Your destination may be IMC?
Click to expand...

They don't have to advise anything, but often will inform you in case there's been a change. I've been told my destination has gone IMC enroute (I was 2 hours out still), they asked intentions and I indicated I land earlier if necessary, as it was just lingering coastal fog. I was also advised of a pop up TFR for fire fighting on a trip home (California to Texas).

For weather, just inform ATC you need to check weather on FSS frequency. They'll normally tell you to be back up within 3-5 minutes. In Texas, I often get the next frequency hand off given to me in case of a fumble.
 
danhagan said:
They don't have to advise anything, but often will inform you in case there's been a change. I've been told my destination has gone IMC enroute (I was 2 hours out still), they asked intentions and I indicated I land earlier if necessary, as it was just lingering coastal fog. I was also advised of a pop up TFR for fire fighting on a trip home (California to Texas).

For weather, just inform ATC you need to check weather on FSS frequency. They'll normally tell you to be back up within 3-5 minutes. In Texas, I often get the next frequency hand off given to me in case of a fumble.
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Yabut - what I'm saying is to me this is part of what being the PIC is all about. I can get a weather brief enroute from FSS, I can look it up on my phone(depending on altitude), etc. Presuming we're in a flight where the clouds below are becoming sct to bkn, isn't that something a pilot would naturally do on his own? I'm trying to figure out what FF does about deteriorating weather besides tell the pilot what he can already find.

I suppose there are people who will stare at the purple line all the way until it's time to descend and then 'uh oh - Chango!' moment hits. Does FF make this any different/better?
 
docmirror said:
Yabut - what I'm saying is to me this is part of what being the PIC is all about. I can get a weather brief enroute from FSS, I can look it up on my phone(depending on altitude), etc. Presuming we're in a flight where the clouds below are becoming sct to bkn, isn't that something a pilot would naturally do on his own? I'm trying to figure out what FF does about deteriorating weather besides tell the pilot what he can already find.

I suppose there are people who will stare at the purple line all the way until it's time to descend and then 'uh oh - Chango!' moment hits. Does FF make this any different/better?
Click to expand...

I'd hope every pilot would stay on top of things ... but things change as well. Example below:

I had a trip from Texas to California that the weather forecast wasn't in the same ballpark for what I was running into (rain all across west TX, NM, AZ to CA). Forecast even at departure was for VFR with no rain (just cloudy). Airborne things headed south all the way to Tuscon. At that point a HUGE convective area developed from PHX to Blythe and I had to land to re-assess. (Weather check #2 by phone, not counting FSS on board). Looked like I could remain just south of I-10 and miss much of the problem area. Once airborne (like 5 minutes later), it became evident that this plan wasn't going to work. This was on July 4th and I happened to be the only AC ABQ CTR was handling in my sector. He asked if I could take an alternate route towards Yuma, had me wait a few minutes and then cleared me through ALL restricted airspace between Pima AZ and Yuma. Without that clearance, there was no way I was going anywhere the rest of the day (without an even bigger diversion) as the weather was pinned up against the RA areas.
 
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