(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?
(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.
Hello,
When you are preparing a baseline in the beginning, what is your practice to insert the anticipated weather or miscellaneous delays into a schedule?
You put lags? if so where?
You put an overall delay item in the end and decreases it as delays occur?
Or what do you do and why / why not?
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Thank you Zoltan!
I expect that nothing happened in 1976 also.
CPM was developed in 50-s but it does not take into account resource and other constraints. Large Government projects may have unlimited resources but it is not true for all projects. Today project management software is used everywhere and for medium and small projects and portfolios also. And so it is not enough to follow principles of 50-s. New challenges shall be met.
And FYI: current version of Primavera (P6) is an improvement of P3e. P3e appeared in 1999 after Primavera bought Eagle Ray - the package developed by another company and presented in 1998. This package got new name and new owner.
So P6 was developed 5 years later that Spider Project.
It does not matter but it looks like you are interested in the history of project management software development.
Regards,
Vladimir
guys I was trying to be sarcastic yes Primavera started in 1983 howver it is based on the same principles and techniques developed in the late 1950s by Dupont and American company and further in the 1960s that put a man on the moon. Spider came out in 1993 which is 10 whole years after Primavera was launched.
- Please remember that some of the most sophisticated and complex projects were and are still being built in the USA using this "not very functional software from the 1960's" This was even the case as the USA was the 1st county to put a man on the moon in the late 1960's.
The timeline I got is quite different.
Dear Zoltan,
please inform us when Primavera was launched to the market. If I remember correctly in 60-s the whole world used only mainframe computers. Do I understand you properly that Primavera mainframe version (?) was used in 60-s?
And please give me the reference to 1976 discovery of the solution to the weather problem in Russia.
Besides I did not know that Spider was developed and used in 60-s. Can you supply us with the reference to the source of this sensational information.
I did not find this information though have read the full thread following your advice.
Thank you and Best Regards,
Vladimir
Well 1969 USA with the help of Primavera scheduled and landed on the moon and since Russia was using Spider it took another 7 years how to figure out how to add weather to the schedule and the laneded 7 years later in 1976.
Read the ful thread
An interesting discussion!
Zoltan, you wrote: "This was even the case as the USA was the 1st county to put a man on the moon in the late 1960's while Russia couldn’t figure out the weather days until 1976. It took 7 years to figure out how to schedule it with Spider. It is so easy with P6."
OK, Russia was the 1st country that launched a satellite and the 1st man into the space. Large projects happen not only in the USA, though I truly respect the USA achievements.
In any case both Spider Project and Primavera were developed much later. And please explain what did you mean mentioning that "It took 7 years to figure out how to schedule it with Spider"? What happened in 1976 that told you that Russia discovered the secret how to deal with the weather? It looks like you know about Spider Project and project management in Russia more than me.
Please explain, it looks like you have very interesting information hidden from others.
Regards,
Vladimir
I used your "quote' "American" I certainly know is should have said English.
To account for rain in minutes is overkill and not necessary.
Please remember that some of the most sophisticated and complex projects were and are still being built in the USA using this "not very functional software from the 1960's" ...
... This was even the case as the USA was the 1st county to put a man on the moon in the late 1960's ...
... while Russia couldn’t figure out the weather days until 1976. It took 7 years to figure out how to schedule it with Spider. It is so easy with P6.
By the way it would be better to say "do not use"'instead of "use not" that's proper "American".
You say "That is because most Americans use not very functional software such as MSP and P6, software designed on the scheduling theories of the 1960's, incapable of creating better models."
Please remember that some of the most sophisticated and complex projects were and are still being built in the USA using this "not very functional software from the 1960's" This was even the case as the USA was the 1st county to put a man on the moon in the late 1960's while Russia couldn’t figure out the weather days until 1976. It took 7 years to figure out how to schedule it with Spider. It is so easy with P6.
By the way it would be better to say "do not use"'instead of "use not" that's proper "American"
no one in the USA is going spread the rain in fractions of an hour to the same percentage of expected rain days, say 5 rain days out of 30 = 16.7% or 10 minute per hour.
That is a flawed approach and the anticipated adverse weather days are HIDDEN within the calendars times. This will not fly in the US.
OK I am talking USA
no one in the USA is going spread the rain in fractions of an hour to the same percentage of expected rain days, say 5 rain days out of 30 = 16.7% or 10 minute per hour.
That is a flawed approach and the anticpated adverse weather days are HIDDEN within the calendars times. This will not fly in the US.
- "but you cannot claim that day as an adverse weather day unless it delays 50% or more of your work day - FACT as per scheduling specification"
Because you do not know which day of the month will rain [all you have is an average] the idea of using specific rain days is a raw approximation. If your software gives you more granularity you can spread the rain in fractions of an hour to the same percentage of expected rain days, say 5 rain days out of 30 = 16.7% or 10 minute per hour. This is a methodology used by some Spider Project schedulers. The calculations and adjustments are similar but this method do not discard some predicted impact if it does not rain on the "planned" rain day.
"If weather stops work then the work is delayed - fact.
I agree but you can not claim that day as an adverse weather day unless it delays 50% or more of your work day - FACT as per scheduling specification
When MOST planning units are days I would say that a 30 minute limit can is precise enough.
"If weather stops work then the work is delayed - fact.
"Restrictions in P6 software do not allow precise work stoppages." NOT TRUE I have 2 options I can use suspend and resume or I can add a non-working time to my calendar as low as 30 minute intervals on a daily basis.
.
"If weather stops work then the work is delayed - fact - so you must keep to the facts." NOT TRUE you can not actually claim the day as an adverse weather daa if it did not effect 50% or more of your work day. So you are tellimg me if it sprinkles to 2 minutes and stops you can claim the whole day ? Most Specifications do not permit this.
"Restrictions in P6 software do not allow precise work stoppages." NOT TRUE I have 2 options I can use suspend and resume or I can add a non-wrlign time to my calendar as low as 30 minute intervals on a daily basis.
Hi Rafael
Abslutely Correct.
Best regards
Mike Testro
okay so i must have two calendars, one normal calendar and the other is a weather affected calendar. and in the second one I must insert days as non working days, to compensate for weather delays. did I understand correct so far?
and if it rains that number of days, then it is fine but what if it rains less and we do work that day?
Be reminded that the rain calendar will adjust the schedule as an activity moves in/out rain seasons. If an activity is delayed from non rain season to rain season some additional activity time will surface from the model.
If weather stops work then the work is delayed - fact - so you must keep to the facts. Also its not just rain - any type of adverse weather will stop work - Wind - Frost - Heat - Fog all have the same effect. And its not just the weather period - you have to calculate the lay down and start up loss of productivity.
Restrictions in P6 software do not allow precise work stoppages.
It is a misconception that you shall use a singe schedule for all purposes, the schedule that includes allowance for rain calendars shall be used for contract management [usually called the Contractual Baseline or Baseline for short] while a update version without any padding shall be used for field management. Ideally both shall be transparent to all parties though at times it is necessary to recur an additional Ghost Schedule.
or it atuomatically updates for both when update weekely?
okay so i must have two calendars, one normal calendar and the other is a weather affected calendar. and in the second one I must insert days as non working days, to compensate for weather delays. did I understand correct so far?
and if it rains that number of days, then it is fine but what if it rains less and we do work that day?
Hi Zoltan - Rafael
If weather stops work then the work is delayed - fact - so you must keep to the facts.
Restrictions in P6 software do not allow precise work stoppages.
If you want to use it then Asta will record stoppages to the nearest second in time.
Also its not just rain - any type of adverse weather will stop work - Wind - Frost - Heat - Fog all have the same effect.
And its not just the weather period - you have to calculate the lay down and start up loss of productivity.
Best regards
Mike Testro
As I stated before using >0.1in is not good it should be higher, somewhere near >0.5in. Perhaps the >0.1in is the proposed number by dishonest media that wants you to project many many expected rain days as for you not to be able to claim any rain day.
weather must impact at least 50% of your work day to be considered as an actual adverse weather day.
you have 2 scenarios
scenario #1
it rains for 5 minutes and you can get back to work
scenario #2
it rains for 5 minutes and you can get cannot back to work
it does not matter how long it rains but if you can work on critical path items or not.
Rafel has it correct to use historical rain days per month using rain above 0.1
in the US we use NOAA to get or historical data and our actuals the historial data is usually in the specificaitons if not we go here to obtain it
Mike,
Most specifications at home require you consider historical rain data but do not specify what is the threshed for rain to be considered a delay event. The threshold is for planning purposes, to forecast the future.
If we calculate as historical rain days per month using rain above 0.1in versus 0.25in the difference is huge. At my location .01 threshold yields 112 days of rain per year, the value used in most examples while .25 threshold yields 35 days of rain per year which makes more sense.
The best specs I have seen are very simple they tell you how many days of rain are considered the norm for purpose of negotiating rain impact.
Rafael
Hi Rafael
"but most fail at the basic assumption on what is the threshold required to consider rain as a delay event."
There is no basic assumption.
If weather stops work it causes delay.
It is not a delay event unless the stoppage is more than could have been anticipated.
Non weather delays have an impact if it delays the work into an anticipated weather stoppage such as the Monsoon Season.
Best regards
Mike Testro
There are many variations on methods to model the impact of weather but most fail at the basic assumption on what is the threshold required to consider rain as a delay event.
Good Luck
Weather sensitive work should be properly assigned to a “Weather Sensitive Calendar”. Anticipated adverse weather is programmed into the CPM network calendar.
Often there is work that must be performed outdoors. This work can be subject to temperature, moisture, freezing and a host of other restrictions. Any work that is weather sensitive should be assigned to a weather sensitive calendar.
The number of Monthly mean Anticipated Adverse Weather days is typically calculated based off of historical data that can be provided by National Oceanic and Atmospheric Administration (NOAA). This calculation is based on geographical locations and will list the Monthly Anticipated Adverse Weather Delay Work Days. This is often listed in the scheduling specification.
When creating a weather sensitive calendar the number of Monthly Anticipated Adverse Weather days should be indicated as non-working days on a month by month basis.
Hi Ahmet
Put in non work days in the calendar and then adjust the allowance with what actually happens.
You need two calendars:
1 for weather affected work
2 for inside work
You may need a third if wind affects the toqer crane.
Best regards
Mike T.
Email: PPadmin@planningplanet.com
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