Route overview
3 min read

Today’s trip, from Chattanooga, Tennessee, to Greensboro, North Carolina, is perfect for general aviation. Instead of a six hour drive along the winding roads of the Appalachian Mountains, you can fly your Mooney there in less than 90 minutes. That’s assuming the weather cooperates, of course, and a quick look at ForeFlight suggests there might be some work involved. Your airplane is well-equipped with datalink weather and a good autopilot, and you are both instrument current and proficient, but is that enough today? Read the weather briefing below and decide what you would do.

Overview

The Maps page in ForeFlight shows your route cutting right across a cold front, with rain and IFR conditions throughout eastern Tennessee and western North Carolina.

Route overview

The surface analysis shows the cold front is bearing down on eastern Tennessee, while you’re currently in the warm front area ahead of it. It’s all spinning off a low pressure system over Illinois, and there’s another front just behind the first one.

Surface analysis

The 12-hour prog chart shows the front moving through Knoxville and Asheville this afternoon, although not much convection is forecast.

12 horu prog

By tonight, the rain seems to be breaking up just a bit and the front should be right over your destination.

18 hour prog

Radar and satellite

Given that big picture overview, it’s no surprise the radar shows a long line of rain stretching from northeast to southwest. So far it looks like just rain, but some areas north of your route could be convection or at least heavy rain.

Radar

Infrared satellite shows a lot of thick clouds, but mostly far to the north of your route. Things appear less well organized in North Carolina.

IR satellite
The graphical cloud forecast suggests ceilings ranging from about 800 feet to 1500 feet, with tops in the mid-teens. You’ll definitely be IMC for most of the flight today.
GFA chart

Ice and turbulence

With a lot of mountains along your route, you know you’ll be flying reasonably high. That means icing could be a threat, but fortunately the freezing level is fairly high today—at least for now, as warm air is being pushed up from the south. You should be above freezing until at least 10,000 feet.

Freezing level

As expected, there is no ice forecast below about 11,000 feet along your route.

Icing

Turbulence may be a different story. There is an AIRMET for turbulence and low level wind shear, not surprising given the fast-moving cold front.

AIRMETs

The GTG forecast isn’t terrible, but there definitely might be some bumps over the mountains with all that wind blowing.

Turbulence forecast

Pilot Reports

A quick look at the PIREPs overview chart suggests the rides may not be that bad. Most of the moderate turbulence is up in the flight levels.

PIREPs

Digging into some specific PIREPs, the only relevant one for turbulence was light chop at 3500 feet near Knoxville, and that’s in the heaviest rain.

Turbulence PIREP

Another PIREP near Knoxville confirms the tops are in the teens—it’s unlikely you’ll get on top today.

TN clouds PIREP

Further south, though, tops are reported at 7800 feet—maybe the reality along your route is somewhere in between?

Atlanta PIREP

Closer to your destination, a pilot report confirms the 1400 overcast layer.

PIREP GSO

Text weather

It’s an IFR day, so the METARs and TAFs are critical. Weather at your departure airport isn’t great, with a solid IFR ceiling and visibility. But it’s certainly above approach minimums and the forecast suggests improving weather over time.

CHA text weather

En route, conditions are IFR to marginal VFR but not that bad—visibility seems to be very good until you get well into North Carolina.

METARs

It’s lower at your destination, but once again above minimums and with light winds. The forecast at GSO, like it is at CHA, is for improving ceilings and visibilities.

GSO text weather

Decision time

It’s time to make the call: is this flight a go or a no go? It will definitely be conducted in IMC if you go, and possibly with some bumps over the mountains. You’ll probably be on the gauges from shortly after takeoff until short final. But it doesn’t appear there is any convection or icing, and almost every airport along your route is above IFR approach minima.

What would you do? Add your comment (and explain your reasoning so others can learn) below.

Latest posts by John Zimmerman (see all)
27 replies
  1. Brad Koehn
    Brad Koehn says:

    For me this is a solid go. It’s similar to a flight I did in December from NEW to CGI; there were some periods of heavy rain and moderate turbulence, but nothing the plane and pilot couldn’t handle. Temps remained well above freezing so no icing to worry about. 3.5 hours of actual and a GPS approach, what could be better?

    Reply
  2. Larry F Baum
    Larry F Baum says:

    Not an ideal day, but a doable flight in a Mooney with the current/proficient pilot. Probably would file for 9k ft to be on top or between layers most of the way. Might be bumpy on the decent into KGSO, but not too bad. No ice is a good thing. Would look at airports east and southeast of KGSO as potential outs should there be any issues.

    Reply
  3. Kelly Horton
    Kelly Horton says:

    Probably would go but would have an escape plan in case things don’t go as planned. Did a similar flight a few weeks ago and it turned out just as planned but that is not always the case.

    Reply
  4. Andy Brown
    Andy Brown says:

    Question unaddressed is purpose of the trip, perhaps. While it is a doable flight for most IFR proficient pilots, any issue I associated with the weather changes that dynamic quickly. You’re over mountains in solid IFR when the engine sputters…what now?

    Turbine or twin and I’d go any day of the week. Single piston (as a guy who has had two conk on him, one at altitude in IFR) and I’d be asking myself “why not wait for this front to pass over?”…

    Reply
  5. Paul
    Paul says:

    Good morning. Like anything else in life, it depends. If I were a low time IFR pilot I would defer the flight, otherwise, given the equipment I have and if had plenty of IFR experience in weather, I would launch. My concerns would be turbulence passing the cold front and heavy rain (which could get worse) and if I had to climb higher for whatever reason, icing is possible. I would also carefully monitor the weather at destination, which could also become worse than the forecast. A definite safe alternate would be in my plan B. Thank you.

    Reply
  6. Low Wings
    Low Wings says:

    Andy Brown has nailed it! The Reward/Risk ratio hovers near 1.0, maybe a bit negative depending on what weather and other equipment is installed and operational in the Mooney and the overall condition of the aircraft and pilot. There is a lot riding on multiple systems with a single point of failure!

    I’m thinking about the old bromide “Pilots that crash in bad weather are typically buried three days later in sunshine.” Gravity always wins!

    Reply
  7. Pier Dutcher
    Pier Dutcher says:

    John didn’t specify what type of Mooney it was. I owned a little “C” model. With two people and some baggage and full fuel, climbing above 10,000’ was a bit iffy. I now have a Bravo with TKS – a whole different story. This trip would be a “go” for me.

    Reply
  8. Rankin Whittington
    Rankin Whittington says:

    A direct route from CHA to GSO takes you over high, very inhospitable mountains. Mountain obscuration is certain. So when that single engine throws a rod at 9,000 feet, you will have a very few minutes to face the fact that you will hit the mountain at the moment you see it. The worst of the mountains can be avoided by flying southeast initially, but it’s a no-go for me.

    Reply
    • Marc Rodstein
      Marc Rodstein says:

      I agree completely. In flat land this would be a go for me, but I have flown over those mountains under VMC, and they are scary even then. In IMC, no way. There is always tomorrow.

      Reply
  9. Fortson Rumble
    Fortson Rumble says:

    Probably a no go, but only because I’m retired and don’t truly HAVE to be anywhere. More of I can wait so I’ll wait. If I really wanted to be there, I’d go – not with “get there ittis” I fly into KRHP often and that’s not a great area to lose an engine in hard IFR but good or bad I fly IFR in a single and the mountains do add a bit of pucker to the flight. It DOESN’T make me change my flight plans but I have a parachute for the plane (182) and I’m always glad for the option if I lose my engine in IFR.

    Reply
  10. David
    David says:

    I’m a probably not due to MTN OBSCN in a single engine. There just isn’t an out if the fan up from quits working. I may go if the route south of the high mountains in TN is open without getting too deep into ATL TRACON. I want just a bit of clearance between the cloud base and the ground to give a chance to avoid cumulus granitus.
    At night – not with this guy.

    Reply
  11. José Serra
    José Serra says:

    For me there are a lot of things to consider:
    1) is that flight absolutely necessary to be done that day?
    2) how are the forecasts for the subsequent days?
    3) how is the sistem of the aircraft to deel with ice?
    4) although currently and proficient in IFR, the pilot must be absolutely sure that the aircraft is in perfect conditions, of course in a normality of situations;
    5) anyway, even the less conceived anomalies could occur and, considering the weather situation, a plane B, C and D must be drawing and with all that implies (weather in airports on route, etc).
    6) the go decision is doable, but, for me, only if I was lead to the conclusion that the flight should, for a strong reason, be made in that day.

    Reply
  12. Stephen Shore
    Stephen Shore says:

    Multi or turbine no issue. Single engine piston over that terrain “nope”. Not enough time to find a suitable place to put down the airplane. Cold fronts are usually the most challenging weather to overcome in a single piston.

    Reply
  13. Joey
    Joey says:

    Go. Why did you get an instrument rating and a Mooney if you aren’t going to fly on a day like this?

    Above minimums all the way (and forecast to get better if anything), no ice, no storms. Just a weak little cold front. Hit file and go fly.

    Reply
  14. Rick Junkin
    Rick Junkin says:

    This is a “go” with the addition of ODF Foothills VOR to the route of flight. That only adds about 20NM and takes me across the windward side of the foothills well south of Clingman’s Dome and other 6K’+ terrain and puts me in a much better starting point for identifying options if things don’t go as planned. In addition to creating options, this is my back yard and we don’t fly over the Smoky Mountains below 10K’ when the winds are blowing, even VFR. The winds aloft aren’t presented but the gusty surface winds and LLWS/turbulence forecasts give me pause. BTDT.

    As others have pointed out, the model of Mooney is a consideration. If it’s an oxygen-equipped turbo that would be cruising in the high teens or above then the direct flight would be possible using altitude as the mitigation for getting above the mechanical turbulence over the mountains as well as being able to immediately turn south toward hospitable terrain and airports in the event of an emergency. Icing would become a risk that a FIKI TKS airplane would mitigate.

    Reply
  15. Paolo Bernardi
    Paolo Bernardi says:

    Above my minima so no go. But even if AIRMET gives me a pause. Pireps are from ships bigger than the Mooney so turbulence will be heavier. Apps are cool but even if I were a very experienced and in my minima I would take the time after going all the data and chat with the briefer.. They might catch something I missed. Myself I do use app but I like snooping Aviation Weather and 1800 wx then call a briefer

    Reply
  16. Jack
    Jack says:

    We fly out of east tn and have to cross over the Appalachians every time we fly south or east. There is a corridor just south and west of Asheville near Hot Springs that lowers the terrain considerably and follows the road thru the passes. Rick nailed his comments about the winds. Even on a calm VFR day, 7500 feet is a minimum and still you will get kicked around in a 172. With the low level turbulence associated with the cold front, It would be a definite no go for me. On a CAVU day, there are very little options to an engine failure with a successful outcome in the mountains.

    Reply
  17. Manuel Rojas
    Manuel Rojas says:

    Well, 30+ years ago this would be a Go for me, now retired from flying mostly jets and assuming I would still be active, this is a No-Go in a piston single engine with no De-Icing, whether the flight be needed today or not.

    Reply
  18. C. Woodford
    C. Woodford says:

    Staying on the ground. I’ve been over those mountains in a single in turbulence and rain, and I ain’t gonna do it again. As a retired oldster, I have the benefit of flying for pleasure, and that flight won’t be fun. Over the flats with plenty of escapes it would be fine, but I don’t see that other airports in the mountains will provide much of an “out.” Coward though I admittedly am, IFR over that terrain just adds another risk factor that I would like to avoid.

    Reply
  19. M Piersol
    M Piersol says:

    Weather looks better later- large high pressure on the way. Though I could do this in my twin without a lot of issue, why. If I had to go this day, at least later in the day looks better odds to me.

    Reply
  20. Don W.
    Don W. says:

    Pros: 90 min flight, autopilot, proficient pilot, ice (probably) not an issue, vis & ceiling improving
    Cons: Single engine IFR over mountains! 38kt 2000′ wind shear! Winds at destination increasing (14G25 kts)
    Unknowns: Mission, Winds aloft, aircraft (model, maintenance profile, O2 availability)

    I’m uncomfortable with this flight primarily because if the engine quits at the wrong time it will likely be fatal, and I’ve had an engine quit on me. If you really needed to fly this, I’d suggest heading to the south over lower terrain, and carefully planning the flight to have glide distance to an airport all the way. If things go south, and you’re breaking out low with a dead engine, you’ll want to have a pretty good idea that there is a runway in front of you. — Don

    Reply

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