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#1 PhillyRN

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Posted 09 October 2008 - 09:25 AM

I have been asked to gather information from other programs, & would especially like to hear from pilots. We are looking into making changes to our weather mins & already know what we will use for basic information, essentially CAMT mins. The question has come up about dew-point spread. Do you look at it? Does it matter? Do you incorporate this in your go / no go decision? if so how? Please ask your pilots or ask them to respond. I would be very grateful.

PhillyRN
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#2 C3 Inc.

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Posted 10 October 2008 - 02:04 AM

I have been asked to gather information from other programs, & would especially like to hear from pilots. We are looking into making changes to our weather mins & already know what we will use for basic information, essentially CAMT mins. The question has come up about dew-point spread. Do you look at it? Does it matter? Do you incorporate this in your go / no go decision? if so how? Please ask your pilots or ask them to respond. I would be very grateful.

PhillyRN


As a Commercial R/W Pilot myself and Instrument Instructor, I would suggest a dew point spread of anything less than 11 to be conservative. Untill we put our feet down on this weather and stop pushing the envelope...we will keep having accidents that could have been prevented. And for one of the most preventable occurrences, we need to error on the side of caution. FARS are VERY relaxed when it comes to this, Part 91 even more so. (See and avoid, stay clear of clouds basically, altitude that allows a safe landing in case of a failure) CAMTS are a little steeper...but again when you have a narrow dew point spread, you are asking for carb ice, which will be masked by the effects of the Gov. Gov makes up for the loss of RPM, going unnoticed until failure occurs and loss of rotor RPM is beyond recovery. Solution simple...enter an auto...as long as you recovered the rpm before blades blow back and whack off the tailboom or strike mast...but at night (which is where the majority of incidents are seeming to occur) this in itself poses sometimes lethal consequences.

So, if I am assumming correct, you are in Phila, almost sea level...not too big a deal with density altitudes...but add carb ice to Mount terrain, full weight, full power used, throw night into it...etc, etc...We see the same thing over and again on these issues. Even fully equipped IFR programs with equipment that would make any pilot drool...and the same results can happen, which is usually the crew not coming home. take home message, med crews educate yourselves on weather...stand up if you are not feeling good about it, and use MINIMUMS as just that...minimum. This was one of the areas I understood the least when flying as a paramedic...weather. Some great programs out there too...especially the java on Air Medical Pilots Assoc website. Great tool that takes the area, and lists a green, yellow, or red...based on criteria we input.

Hope that helped a little. Good luck and let me know if you need any supporting documentation on anything...I have a ton of Lit on the subject. (Bell and Eurocopter factory school this year)
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Richard A. Patterson
MBA, NR/CCEMT-P, MICP, FP-C, CFI, CFII, AGI, IGI
Critical Care Concepts, Inc.
www.CriticalCareConcepts.net
Email: info@CriticalCareConcepts.net

#3 BackcountryMedic

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Posted 10 October 2008 - 03:11 AM

Some great programs out there too...especially the java on Air Medical Pilots Assoc website.


Great post.

Do you have the URL for that site? Thanks!
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#4 C3 Inc.

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Posted 10 October 2008 - 12:44 PM

Great post.

Do you have the URL for that site? Thanks!


Sure...it is

http://weather.aero/hems/

Enjoy! I use it all the time. Anyone can work it, play around with input data, variables, etc.

Take care,
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Richard A. Patterson
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Critical Care Concepts, Inc.
www.CriticalCareConcepts.net
Email: info@CriticalCareConcepts.net

#5 marcdurocher

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Posted 13 October 2008 - 02:07 AM

I have been asked to gather information from other programs, & would especially like to hear from pilots. We are looking into making changes to our weather mins & already know what we will use for basic information, essentially CAMT mins. The question has come up about dew-point spread. Do you look at it? Does it matter? Do you incorporate this in your go / no go decision? if so how? Please ask your pilots or ask them to respond. I would be very grateful.

PhillyRN


The temp/dew point spread is invaluable on some flights. Pilots use it frequently. I'm not sure how it would be incorporated into a minimum though. You can have a 3 degree spread and a stable temperature and fly all night. Sometimes the second they converge you are blanketed. All pilots are trained to process this information, but again, I don't know how it would be incorporated into any kind of minimums. I hope this help a little.

Marc D.
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Marc Durocher - Lifeflight Missoula Montana - Helicopter pilot

#6 PhillyRN

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Posted 14 October 2008 - 06:01 PM

Thanks for all the help.
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#7 jdhelicopterpilot

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Posted 25 October 2008 - 03:09 AM

As a Commercial R/W Pilot myself and Instrument Instructor, I would suggest a dew point spread of anything less than 11 to be conservative. Untill we put our feet down on this weather and stop pushing the envelope...we will keep having accidents that could have been prevented. And for one of the most preventable occurrences, we need to error on the side of caution. FARS are VERY relaxed when it comes to this, Part 91 even more so. (See and avoid, stay clear of clouds basically, altitude that allows a safe landing in case of a failure) CAMTS are a little steeper...but again when you have a narrow dew point spread, you are asking for carb ice, which will be masked by the effects of the Gov. Gov makes up for the loss of RPM, going unnoticed until failure occurs and loss of rotor RPM is beyond recovery. Solution simple...enter an auto...as long as you recovered the rpm before blades blow back and whack off the tailboom or strike mast...but at night (which is where the majority of incidents are seeming to occur) this in itself poses sometimes lethal consequences.

So, if I am assumming correct, you are in Phila, almost sea level...not too big a deal with density altitudes...but add carb ice to Mount terrain, full weight, full power used, throw night into it...etc, etc...We see the same thing over and again on these issues. Even fully equipped IFR programs with equipment that would make any pilot drool...and the same results can happen, which is usually the crew not coming home. take home message, med crews educate yourselves on weather...stand up if you are not feeling good about it, and use MINIMUMS as just that...minimum. This was one of the areas I understood the least when flying as a paramedic...weather. Some great programs out there too...especially the java on Air Medical Pilots Assoc website. Great tool that takes the area, and lists a green, yellow, or red...based on criteria we input.

Hope that helped a little. Good luck and let me know if you need any supporting documentation on anything...I have a ton of Lit on the subject. (Bell and Eurocopter factory school this year)



Just wondering what Carb Ice has to do with it? Yes, Carb Ice can be encountered in that situation but most, in fact all EMS helicopters are turbine powered. So, Carb Ice is a non issue.

However, the temp/dew point spread is very important. But you have to consider not just what it is a present time but where it may go. In the afternoon hours you may have a spread that is sufficent but what happens when the sun sets? It gets cooler and the spread will decrease. This will lead to a better chance of clouds and fog. If you fly around coastal areas then that is truly something to look at. On the other hand in the early morning hours you can count on the sun warming things up and hopefuly see an increase in the temp/dew point spread. In which case you can expect the low clouds and fog to start breaking up and moving out of the area. Surface winds will also have an effect. If the winds kick up enough it will lift into a low stratus layer.

I wouldn't be against a Temp/dew point minimum. I should point out though it's not just an issue along the Coastal areas.
JD
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JD

Safety doesn't happen by accident, inspect what you expect.

#8 C3 Inc.

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Posted 25 October 2008 - 04:38 AM

Just wondering what Carb Ice has to do with it? Yes, Carb Ice can be encountered in that situation but most, in fact all EMS helicopters are turbine powered. So, Carb Ice is a non issue.

However, the temp/dew point spread is very important. But you have to consider not just what it is a present time but where it may go. In the afternoon hours you may have a spread that is sufficent but what happens when the sun sets? It gets cooler and the spread will decrease. This will lead to a better chance of clouds and fog. If you fly around coastal areas then that is truly something to look at. On the other hand in the early morning hours you can count on the sun warming things up and hopefuly see an increase in the temp/dew point spread. In which case you can expect the low clouds and fog to start breaking up and moving out of the area. Surface winds will also have an effect. If the winds kick up enough it will lift into a low stratus layer.

I wouldn't be against a Temp/dew point minimum. I should point out though it's not just an issue along the Coastal areas.
JD


Well said. I mentioned it as it came up in an investigation with MSP as a potential cause? I know the Euro Daulphine is twin turbine, but these effects can still occur in the right environment. What I mess still going on there. My heart goes out to those guys and gals and also the Air Angels crews...what a great bunch of folks!
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Richard A. Patterson
MBA, NR/CCEMT-P, MICP, FP-C, CFI, CFII, AGI, IGI
Critical Care Concepts, Inc.
www.CriticalCareConcepts.net
Email: info@CriticalCareConcepts.net

#9 Bubba

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Posted 25 October 2008 - 04:43 AM

As a Commercial R/W Pilot myself and Instrument Instructor, I would suggest a dew point spread of anything less than 11 to be conservative. Untill we put our feet down on this weather and stop pushing the envelope...we will keep having accidents that could have been prevented. And for one of the most preventable occurrences, we need to error on the side of caution. FARS are VERY relaxed when it comes to this, Part 91 even more so. (See and avoid, stay clear of clouds basically, altitude that allows a safe landing in case of a failure) CAMTS are a little steeper...but again when you have a narrow dew point spread, you are asking for carb ice, which will be masked by the effects of the Gov. Gov makes up for the loss of RPM, going unnoticed until failure occurs and loss of rotor RPM is beyond recovery. Solution simple...enter an auto...as long as you recovered the rpm before blades blow back and whack off the tailboom or strike mast...but at night (which is where the majority of incidents are seeming to occur) this in itself poses sometimes lethal consequences.

So, if I am assumming correct, you are in Phila, almost sea level...not too big a deal with density altitudes...but add carb ice to Mount terrain, full weight, full power used, throw night into it...etc, etc...We see the same thing over and again on these issues. Even fully equipped IFR programs with equipment that would make any pilot drool...and the same results can happen, which is usually the crew not coming home. take home message, med crews educate yourselves on weather...stand up if you are not feeling good about it, and use MINIMUMS as just that...minimum. This was one of the areas I understood the least when flying as a paramedic...weather. Some great programs out there too...especially the java on Air Medical Pilots Assoc website. Great tool that takes the area, and lists a green, yellow, or red...based on criteria we input.

Hope that helped a little. Good luck and let me know if you need any supporting documentation on anything...I have a ton of Lit on the subject. (Bell and Eurocopter factory school this year)



You need to do one thing and that is turn in your CPL to the FAA. You obviously have absolutely no experience as a helicopter pilot in the real world outside of Robbies. First of all 11 degree dewpoint spread? Good god that is a normal day with clear blue skys! Carb Ice? Show me ONE EMS HELICOPTER that has a carb on it!!!!!!! Stop talking about things you have no idea about. You are not doing this industry any good by giving misinformation.
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#10 C3 Inc.

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Posted 27 October 2008 - 12:07 PM

You need to do one thing and that is turn in your CPL to the FAA. You obviously have absolutely no experience as a helicopter pilot in the real world outside of Robbies. First of all 11 degree dewpoint spread? Good god that is a normal day with clear blue skys! Carb Ice? Show me ONE EMS HELICOPTER that has a carb on it!!!!!!! Stop talking about things you have no idea about. You are not doing this industry any good by giving misinformation.


1 to 2... I emailed the person offline and also referenced Celcius. Thanks for keeping this topic alive and in the forefront though.

Stay safe,
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Richard A. Patterson
MBA, NR/CCEMT-P, MICP, FP-C, CFI, CFII, AGI, IGI
Critical Care Concepts, Inc.
www.CriticalCareConcepts.net
Email: info@CriticalCareConcepts.net

#11 Wally

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Posted 27 October 2008 - 08:09 PM

1 to 2... I emailed the person offline and also referenced Celcius. Thanks for keeping this topic alive and in the forefront though.

Stay safe,


Parse words and split hairs if you like, but you're in way over your head...
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#12 JPST

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Posted 08 November 2008 - 07:41 PM

I have been asked to gather information from other programs, & would especially like to hear from pilots. We are looking into making changes to our weather mins & already know what we will use for basic information, essentially CAMT mins. The question has come up about dew-point spread. Do you look at it? Does it matter? Do you incorporate this in your go / no go decision? if so how? Please ask your pilots or ask them to respond. I would be very grateful.

PhillyRN


I believe all pilots look into a dew-point spread especially at night. But it is not simple thing as 11 degrees or more" unless you don't mind missing perfectly doable flights. The weather pattern differs based on where. The terrain, water/ground ratio, distance from ocean/large open water, and etc affect significantly how the ceiling and visibility end up to be. Even we have an aviation weather forecast available to us, depending on the particular condition, you can tell the forecast won't be accurate if you know the local weather pattern. Almost all locations have one of those places known to be lower weather conditions than other places. Even nearby airport might be calling 200~300 feet above minimum. You almost know that you will encounter lower ceiling than it is reported especially at night. That knowledge is only available at local level. The weather minimum should be local and aircraft capability independent in my opinion. If you need a very accurate and efficient weather minimum or guideline, I would ask several local pilots who has been flying at least five years locally. You should get very similar numbers from those folks.
And if you read any of carb icing thread, please ignore that. It only happens on piston carburetor equipped engines. Turbine engines can have inlet icing. But most of them are equipped with anti-icing system or has an operating limitation in order to avoid it.
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#13 C3 Inc.

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Posted 09 November 2008 - 01:30 AM

I believe all pilots look into a dew-point spread especially at night. But it is not simple thing as 11 degrees or more" unless you don't mind missing perfectly doable flights. The weather pattern differs based on where. The terrain, water/ground ratio, distance from ocean/large open water, and etc affect significantly how the ceiling and visibility end up to be. Even we have an aviation weather forecast available to us, depending on the particular condition, you can tell the forecast won't be accurate if you know the local weather pattern. Almost all locations have one of those places known to be lower weather conditions than other places. Even nearby airport might be calling 200~300 feet above minimum. You almost know that you will encounter lower ceiling than it is reported especially at night. That knowledge is only available at local level. The weather minimum should be local and aircraft capability independent in my opinion. If you need a very accurate and efficient weather minimum or guideline, I would ask several local pilots who has been flying at least five years locally. You should get very similar numbers from those folks.
And if you read any of carb icing thread, please ignore that. It only happens on piston carburetor equipped engines. Turbine engines can have inlet icing. But most of them are equipped with anti-icing system or has an operating limitation in order to avoid it.


Did you even go to school or graduate with a GED? Your grammer is as bad as it is on JH. Nice reply...three weeks later. Welcome to FW...see you joined today, go back to JH where you belong.
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Richard A. Patterson
MBA, NR/CCEMT-P, MICP, FP-C, CFI, CFII, AGI, IGI
Critical Care Concepts, Inc.
www.CriticalCareConcepts.net
Email: info@CriticalCareConcepts.net

#14 C3 Inc.

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Posted 09 November 2008 - 06:11 AM

I believe all pilots look into a dew-point spread especially at night. But it is not simple thing as 11 degrees or more" unless you don't mind missing perfectly doable flights. The weather pattern differs based on where. The terrain, water/ground ratio, distance from ocean/large open water, and etc affect significantly how the ceiling and visibility end up to be. Even we have an aviation weather forecast available to us, depending on the particular condition, you can tell the forecast won't be accurate if you know the local weather pattern. Almost all locations have one of those places known to be lower weather conditions than other places. Even nearby airport might be calling 200~300 feet above minimum. You almost know that you will encounter lower ceiling than it is reported especially at night. That knowledge is only available at local level. The weather minimum should be local and aircraft capability independent in my opinion. If you need a very accurate and efficient weather minimum or guideline, I would ask several local pilots who has been flying at least five years locally. You should get very similar numbers from those folks.
And if you read any of carb icing thread, please ignore that. It only happens on piston carburetor equipped engines. Turbine engines can have inlet icing. But most of them are equipped with anti-icing system or has an operating limitation in order to avoid it.


Yes...many are equipped with an anti-icing system that conducts hot air to the compressor front-support struts to prevent ice forming on the struts. The system is entirely separate and independent of any other bleed air system. The ENGINE anti-icing system must BE TURNED ON BY THE PILOT. As air passes through the compressor, it is compressed. As a result of this compression, the air is heated and is a source of hot air required by the engine anti-icing system. In the medical world, we refer to this as Charles' gas law...dealing with temp and this reduced pressure, as in this venturi situation. I did not think it was neccessary to get this deep into it...but you brought it up. As for your dew point reference...ITS CALLED A TYPO...and was clarified with the individual.

I know you have made a huge ordeal of this on other websites and I applaud your bringing attention to the safety issues we are faced with. Maybe if we keep talking about it long enough, someone will hear and make some changes?

Thanks for the information...
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Richard A. Patterson
MBA, NR/CCEMT-P, MICP, FP-C, CFI, CFII, AGI, IGI
Critical Care Concepts, Inc.
www.CriticalCareConcepts.net
Email: info@CriticalCareConcepts.net