PEM Tropics-B P3-B Status Updates

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(updated 4/1/99)
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Updates: 4/1/99, 3/31/99, 3/22/99, 3/17/99, 3/12/99, 3/8/99, 2/27/99, 2/19/99 Planning Meeting, 2/19/99, 2/15/99, 2/6/99, 2/2/99, 1/25/99

1/25/99- The P-3B was delayed by 10 days in returning to Wallops from the Lockheed maintenance facility in South Carolina. The P-3B was originally scheduled to return to Wallops on January 6, but arrived at Wallop Friday evening, January 15. Under our original schedule installation of probes, inlets, etc. were scheduled to begin on the 6th and would have been nearly completed prior to beginning rack upload. More importantly, the modification to the power distribution system was scheduled to begin on the 6th and be well underway by now. The current estimate is that the power panel mods will require from 2 to 3 weeks to complete. This work is required because the new power distribution system will be about 500 lb. lighter, more reliable, and will generate less heat. The lighter weight of the new power distribution system has already been assumed in our current estimate of the aircraft zero fuel weight and we are still slightly over the weight limit. The power panel mods are critical for this deployment. Wallops management has been briefed on the delay in return of the P-3B and its potential impact on the integration and deployment schedule. They have agreed to make sure that resources are available in an attempt to make-up the lost time and we will plan on a 7-day workweek during the integration period.

Another issue adding uncertainty to the P-3B schedule is the fact that two of the P-3Bs engines are currently operating below the minimum acceptable power rating and a third is operating just at the minimum power rating. Over the weekend the Wallops folks, along with personnel from the company that recently installed turbine blades in these three engines, were scheduled to conduct ground power tests to resolve the low engine power. Unfortunately these tests were delayed until late Monday, 25 January. Tests will in all probability continue through Tuesday.

Rack upload and instrument installation is underway. The forward racks (Eisele and Clarke) and racks along the right side of the aircraft have been installed (Project Data, Blake, and Talbot), along with many of the inlets. Racks along the left side of the aircraft will begin loading after the aircraft is returned from the ground tests. Mods to the power converters were delayed over the weekend and will continue to delay getting aircraft power to the instruments.

It's not entirely clear what impact all of the above will have on the deployment schedule. We do have some constraints that limit the options we have in revising the deployment schedule. The return date for each aircraft is fixed, as per the current return dates, we have only a 3-week window (March 1 - March 23) on Christmas Island with sufficient hotel rooms to accommodate the P-3B deployment team. While there are still some major uncertainties associated with the P-3B that may severely delay our deployment, it appears on paper that if all goes well we may be able to make our March 1 arrival date on Christmas Island. This will require a slightly accelerated test flight schedule, shortening the packing schedule, and only two nights in Hilo on the way to Christmas Island. However, if one takes a more pessimistic (or realistic) view, then our arrival on Christmas Island may be delayed by up to a week.
2/2/99- Ground test of the P-3B's engines were completed late on the evening of 28 January, 1999. The results indicate that one engine will have to be replaced (i.e. overhauled). A replacement engine is currently in the process of being overhauled and is anticipated to be shipped to Wallops by February 12, 1999. Installation of the engine is anticipated to be completed by February 20, followed by a Functional Check Flight (FCF) on February 22. Assuming, that the P-3B is returned to flight status after the FCF, integration will proceed as per the updated P-3B integration and deployment schedule posted on the PEM-Tropics B Home Page. Integration of the instrument payload has moved very smoothly over the weekend with all racks now in place. The few remaining installation issues include internal bracing for the Talbot probes, improved cooling ducts around several racks, exhaust pluming, and completion of the power converter mods. We anticipate that installation of all instruments and the power panel mods will be complete by the end of this week.
2/6/99-As reported earlier,the P-3B's deployment schedule has been slipped by one week as a result of the requirement to replace one of the engines on the P-3B. Late this week it was learned that an additional engine will also be replaced. Both engines are currently at the facility performing the work and both are scheduled to be returned to Wallops by Feb 16, and installed on the P-3B by February 20. These are the dates that were used to developed the revised P-3B schedule that was posted on the PEM-Tropics B home page late last week. The additional engine change is not expected to have an impact on the revised P-3B schedule.
2/15/99-As a result of the slip in the P-3B deployment schedule, we have lost the military cargo airlift originally scheduled to transport PI supplies and spare parts to Christmas Island. We are now exploring options for contracting with a commercial carrier to provide this transport duty. A dedicated cargo flight from Wallops-Hilo-Christmas, then Christmas-western Samoa-Tahiti, and finally from Tahiti-Honolulu-West Coast-Wallops is planned. Since the cargo flight from Wallops will be a commercial outfit, it will not have permission to land at Dryden. We anticipate that the P-3B will stop over at Dryden with the cargo flight at some close-by airport.

Wallops reports that the replacement of the two engines on the P-3B is on schedule, however replacement of the second engine will not take place until later in our test flight schedule. One engine will arrive at Wallops February 16, and will be used as a replacement for the engine that during the ground test indicated output power well below the acceptable level of 95%. This engine is anticipated to be installed by February 20, followed by a Functional Check Flight and the Engineering Check Flight as currently posted on the P-3B integration schedule.

The second engine scheduled for replacement prior to the P-3Bs deployment tested at 95.8% output power during the ground power checks. The current plan is to conduct the first PI test flight on February 24, after completing replacement of one of the engines, but with the 95.8% engine in place. The replacement for the 95.8% engine is expected to arrive by the 24th and would be installed between the 1st and 2rd PI test flight. It is anticipated that the 2nd test flight may be slipped by at least one day.

The in-hanger full power check out is scheduled for February 18th, and a flight planning meeting is scheduled to be convened 9:30 am, February 19, 1999 at Wallops.
2/19/99- Late Thursday afternoon, Wallops flight personnel were notified by Al Diaz, GSFC Director, that all aircraft operations at Wallops were terminated until "…reports of potential continuing concerns with safe operations of aircraft…" are reviewed. No information concerning the nature of the "reports", nor the process to review the reports is available at this time.

Replacement of two the P-3B's engines is continuing with an estimated completion dated of about February 26/27, 1999. Assuming the issues raised by the Diaz letter can be resolved and the P-3B returns to flight status by the 27th, a deployment date on or about March 10 is projected. The P-3B deployment team will continue with a previously scheduled meeting on Friday, February 19 to discuss flight priorities for the remainder of the P-3B deployment.
2/19/99- Minutes of Planning Meeting: The P-3B flight planning meeting was convened at the Wallops Flight Facility, 9:30 am, Friday, February 19, 1999. The initial purpose of this meeting was to review and recommend flight options/objectives for the P-3B deployment in view of the pending 2 week delay in the deployment schedule. Late on the afternoon of the 18th, the Wallops Flight Operations Branch received a letter from the Director of the Goddard Research Center stating that due to "…reports of potential continuing concerns with safe operations of aircraft out of Wallops Flight Facility…", all flight operations at Wallops were terminated until the reports could be investigated. As of COB Friday afternoon, no time schedule, nor understanding of the review process was available. As a result of this stand-down order, discussions at the flight planning meeting were expanded to consider options for a one year slip of the Christmas Island component of PEM-Tropics B.

The meeting was opened with a review of the projected integration/test flight/deployment schedule based upon current estimates for completion of the engine replacements. The P-3B team agreed to reduce the number of test flights to 2, with the provision that the DFRC/Hilo transit flights also be considered test flights. The integration and deployment schedule adopted at the conclusion of the meeting, pending installation of the engine and resolution of the stand-down order from the Goddard Center Director, is currently posted on the PEM-Tropics B home page.

The stand-down order was introduced, but since virtually no information was (or is) available on the source of the "reports" noted in the letter nor the resolution process, it was difficult to do more that speculate on the date that order would be rescinded noted that the engine replacement and PI access to instrumentation onboard the P-3B would not be impacted by the stand-down order.

Joe McNeal opened the discussion on the P-3B options by stating that the Christmas Island deployment was the core component of the P-3B's science objectives and that the an important part of the teams deliberations would be to determine if the number of flights projected for Christmas Island warranted the time and expense of continuing the P-3B deployment. He emphasized that it was the team's decision to determine the minimum number of flights they felt would be required from Christmas Island. He then discussed an option for slipping the Christmas Island deployment by one year. He noted that funds saved by slipping the current P-3B deployment plus funding currently ear marked for a nitric acid intercomparison tentatively scheduled for early FY 00, would make it possible to fund a one year slip in the Christmas Island deployment, with the potential to expand the study by including a ground based component. Joe further noted that the P-3B team could, at the meeting, elect to slip the Christmas Island deployment by one year rather than continuing with an already shortened Christmas Island deployment, or the team could elect to proceed on the assumption that we could deploy and conduct the minimum number of flights at Christmas Island as defined by the team. A decision to slip Christmas Island to CY00 would almost certainly preclude the availability of the GTE Program to fund the P-3B in the TRACE-P mission, tentatively scheduled for CY01. Joe further noted that, in the event that the P-3B does not receive the return to flight order in time to conduct the minimum number of flights at Christmas Island, he would strongly question the scientific rationale for continuing the P-3B deployment to Tahiti, even though he recognized the importance of the combined P-3B/DC-8 flight opportunities that are scheduled at Tahiti. He based this remark, in part, on the assumption that funding would not be available for a P-3B deployment to Tahiti and a one-year slip in the deployment to Christmas Island.

After some general discussion the P-3B team concluded, that in the event that a minimum number of Christmas Island flights could not be conducted, the option to slip the Christmas Island deployment by one year would be favored over continuing with the Tahiti portion of the deployment if it jeopardized a CY00 re-deployment to Christmas Island . Joe noted that the issue regarding funding for both the Tahiti portion of PEM-Tropics B and a CY00 P-3B deployment to Christmas Island would be resolved as soon as possible. Joe also noted that the PEM-Tropics B Science Team was comprised of the P3-B and DC-8 investigators. A slip in the deployment of the P-3B would not alter this, and that data from the DC-8 deployment would be available to all Science Team members as per the data protocol, and likewise, data from a P-3B deployment in CY00 would be available to all Science Team members.

Prior to proceeding with the flight planning, the following Wallops flight rules were reviewed and discussed:
(1) Any flights in excess of 8 hours will require an augmented crew consisting of 2 additional flight personnel. Depending on our final seat count, which will depend upon the aircraft zero fuel weight, one or two investigator seats will be required to accommodate an augmented crew.
(2) Our request to flight a split flight totaling 9 to 10 flight hours (e.g. a 5 hour morning flight-land-4 to 5 hour afternoon flight) has been tentatively be approved with the provision that there be at least 3 hours separating the morning touch-down and the afternoon take-off, and the total crew/PI duty time does not exceed 20 hours.
(3) A non-work day is required after every 13 continuous duty days.
(4) The flight crew duty is restricted to 40 flight hours per 7 days.

After a brief break, Doug Davis lead the discussion to define the science rationale for the flights projected for a Christmas Island deployment, and to define the minimum number of flights from Christmas for a scientifically viable deployment. The menu/objectives of flights presented by Doug are:

· Transit to Christmas: (Coordinated with the DC-8) - Cloud in-flow/out-flow ITCZ (Inter-hemispheric mixing) - Mid-altitude gas to new particle formation

· Christmas Island Locals:
(1) Focused sunrise-to-midday flight (HOx/sulfur/BL/Buf study)
(2) Focused midday-to-post sunset flight (HOx/sulfur/BL/Buf study)
(3) Split Flight - sunrise-to-midmorning/mid-day-to-afternoon (HOx/sulfur/BL/BuL study)
(4) Time History (Sulfur Survey Flight)
(5) Buffer Layer/Free Troposphere (HOx/Sulfur/gas-to-new particle formation study)

· Transit to Samoa (BL O3/HOx flight 2oN to 13oS)

· Transit to Tahiti (BL O3/HOx flight)

Doug emphasized that the list of flights from Christmas Island did not reflect any priority on the flights. After discussion, the P3-B team concluded that at least 4 flight would be required from Christmas Island to make it a scientifically viable deployment.

Prior to adjourning for lunch, it was noted that at least two P-3B measurement teams might be involved in an NCAR mission currently proposed for the February/March/April time period in 2000. Their involvement in the NCAR mission could jeopardize a CY00 redeployment option for the P-3B.

After lunch, Reginald Newell presented additional information for the Christmas Island deployment and science rationale supporting deployment to Tahiti even if additional engine and/or PI instrument problems, or the current hold on Wallops flight operations precludes a Christmas Island deployment.

The concluding discussion by the P-3B investigators resulted in the deployment schedule shown on the GTE Home Page. Note that this schedule does not reflect changes in the DC-8 flight schedule from Hilo, which may be implemented to maximize coordination with the P-3B flights (e.g. coordination with the P-3B transit flight to Christmas Island). There are no plans to change the current deployment date of the DC-8 from Dryden, nor any additional delays in the DC-8's departure from Hilo to Fiji. The P-3B's departure date from Wallops is currently schedule for March 10 with an overnight at DFRC and arrival in Hilo the afternoon of the 11th. The P-3B team concluded that one day in Hilo should be scheduled prior to departure to Christmas Island. Accordingly the departure from Hilo to Christmas is scheduled on the 13th. Arrival at Christmas on the 13th would allow sufficient time to conduct the minimum 4 flights with a departure of the P-3B on the 23rd. An option that would permit an additional flight from Christmas Island would be to extend the stay of the personnel traveling on the P-3B until the 26th. This would allow a flight to be conducted on the 23rd, followed by two days to pack and then the transit to Tahiti. Because of a limitation on the number of rooms that are available during the week of the 23rd, all commercial passengers would have to depart on the 23rd. This option would preclude the Western Samoa stop over.

The consensus of the P-3B team at the conclusion of the meeting was that was:
(1) A minimum of 4 flights would be required at Christmas Island.
(2) In the event that the Christmas Island deployment is not possible, continued deployment to Tahiti should be not be implemented if it adversely impacts the GTE Program's ability to fund a CY00 re-deployment to Christmas Island.
2/27/99- The Mission Readiness Review for the P-3B deployment was held on Friday, February 26, 1999. Pending completion of several relatively minor action items, the P-3B deployment was approved. Arnold Torres, director of the Wallops Flight Facility, also announced that the stand-down order for the Wallops aircraft had been lifted. Ground tests of the P-3B engines are anticipated over this week end followed by the Functional Check Flights and the Engineering Check Flight on Monday. The P-3B deployment schedule posted on the PEM-Tropics Home Page continues to be valid.

All P-3B investigators traveling to Christmas Island via the weekly commercial flight should contact SAIC to confirm the date they plan to travel to Christmas Island (e.g. March 9 or 16). All commercial air passengers will depart Christmas Island March 23th , but the P-3B passengers/crew will continue operations at Christmas until March 26.

Also note that, with the exception of the P-3B flight crew, local transportation for the P-3B stop over in Hilo will be via taxies. This is a change from the information that had previously been published. This is being implemented since we will be in Hilo only about 36 hours and hopefully use of taxies will simplify our arrival and departure process. Taxies are reported to be readily available, so this should not impose a hardship on our ability to get to and from the P-3B parking area. Richard Bendura and Mike Cadena will be in Hilo on Monday and will re-evaluate the availability of taxies relative to use of rental cars.
3/8/99- The first and second tests flights for the P-3B were conducted successfully on March 4 and March 7, respectively. During the first test flight nominal "first-flight" problems pop-up for many of the instruments. On the second test flight most of these problems were rectified. All instrument teams reported ready for deployment on March 10. The initial transit flight on March 10 to DFRC will be a continuation of the test flight series. Transit to Hilo is scheduled for March 11, and deployment to Christmas Island is scheduled for March 13. The DC-8 science team has modified the flight schedule for the DC-8 such that it is now anticipated that coordination between the P-3B and DC-8 will occur on the P-3B transit to Christmas Island and the first P-3B local. This has required an additional delay of one day in the deployment of the DC-8 to Fiji. The revised P-3B and DC-8 schedule is posted on the GTE PEM-Tropics B Home Page.
3/12/99- The P-3B portion of PEM-Tropics B deployed March 10, 1999. The departure from Wallops was delayed for about 3-hours as a result of about 3 inches of snow on the ground the morning of the departure and the need to change an oil filter on one of the engines of the P-3B. Both the P-3B and the DC-8 cargo aircraft arrived in the Dryden area about 7:30 P.M. The cargo aircraft landed at Mojave and the P-3B at Edwards. As a result of the shortened test flight schedule during integration, the P-3B's first transit flight to Dryden was designated as a test flight, but with strong encouragement for as many instruments as possible to be in a data status.

Reg Newell, P-3B mission meteorologist, provided forecasting that permitted sampling of stratospherically influenced air well into the troposphere during this transit flight. All instruments, with the exception of a few, which were still conducting calibrations and performance checks, were in a data status. The transit flight from Dryden to Hilo was an 8-hour data flight, and departed on schedule. Two in progress step profiles were scheduled and conducted. Several instruments reported problems which may impact the quality/quantity of the final data. The P-3B arrived in Hilo 5:00 PM local time, followed by the DC-8 cargo flight about 8:00 PM. A full work day is scheduled for March 12, with a 9:00 A M. departure to Christmas Island planed for March 13.
3/17/99- The P-3B departed Hilo, Hawaii, March 13, 1999, 9:00 AM and arrived at Cassidy Airport, Christmas Island, March 14, 1999, 5:00 PM. (If you have not looked at Christmas Island on a map, you may be surprised to learn that it is located east of the International Date Line, and is one day ahead of Hawaii even though it is nearly at the longitude as Hawaii.) During the P-3B's transit flight, the DC-8 conducted its second local flight from Hilo. The overall scientific coordination between the two aircraft consisted of the P-3B providing in progress profile measurements between Hilo and Christmas Island below about 24,000 ft, while the DC-8 sampled above the flight altitude of the P-3B. The DC-8 returned to Hilo after over flying the Christmas Island area, along a track west of its outbound track. The final 45 minutes of the P-3B's flight into Christmas Island was at 500 ft and designed to survey the uniformity and activity of DMS emission in the Christmas Island study region.

The first P-3B local flight from Christmas Island and the 3rd DC-8 local from Hilo were conducted on March 16, 1999 (local Christmas Island). Both aircraft conducted a sunset photochemistry mission. The P-3B departed Christmas Island approximately 10:45 AM and returned just after sunset at 6:45 PM. The DC-8 departed Hilo 11:00 AM and returned at 9:00 PM. Coordination between the two aircraft consisted of sampling with in the same study region with the P-3B concentrating on the boundary layer and the buffer layer, while the DC-8 focused on the free troposphere.

The DC-8 is scheduled to transit to Fiji, March 17, 1999 (Local Hawaii), while the P-3B is scheduled to conduct a full diurnal photochemistry study March 18, 1999 (local Christmas Island). No coordination between the two aircraft is planned for these flights.
3/22/99- The second Christmas Island local flight was completed 3/18/99 (local time). It was a 2-part flight -- the first part was a 5-hour sunrise flight; the second part a 6 hour sunset flight. Take-off for part one was at 4:30 AM with a 9:30 AM landing. Take off for the second part was at 12:30 PM (same day) and landing about 6:30 PM. Preliminary results suggest the series was scientifically very successful. Ozone and NO were low, and DMS was observed to be relatively high just prior to sunrise. A diurnal anti-correlation between DMS and SO2 similar to that observed in PEM-Tropics A was also observed on this flight. The concentration of SO2 was, however, lower that anticipated based upon the conversion efficiency of DMS to SO2 obtained from the observation during PEM-Tropics A.

The third local flight was completed 3/21/99. This flight was designated as a time-history survey and was designed to sample at several different altitudes while flying into and against the wind directions. The out bound flight track was flown west of Christmas Island along the equator for about 1000 miles. The return east bound track was along a latitude about 2 degrees north of the equator.
3/31/99- The P-3B completed its last local flight on Christmas Island March 24. The focus of this last flight was HOx photochemistry with a take off at 11:30 am and a return at 7:30 pm. March 25 was the pack day in preparation for the arrival of the cargo aircraft and the transit to Tahiti. Both the cargo aircraft and the P-3B departed Christmas by mid-morning. The cargo and P-3B arrived in Tahiti at 4:00 pm and 5:00 pm respectively. During the transit to Tahiti, the P-3B aircraft was struck by lightning and sustained minor damage to the trailing edge of one wing. Measurements of NO during the strike exhibited local concentrations in excess of 1ppbv, along with increases in ozone, carbon monoxide and other trace species. Repairs to the wing were completed on March 29 and a functional check flight was completed the morning of March 30. The first local for the DC-8 aircraft is currently in progress, and the first local flight for the P-3B is scheduled for departure at 8:00 am on March 31. The focus of DC-8 flight is to study the western portion of the SPCZ, while the focus of the P-3B flight will be to study the distribution of trace gases associated with the inflow/outflow of a convective system.
4/1/99- The first P-3B local flight, completed March 31, focused on (1) characterizing the inflow/out flow associated convective systems; (2) Characterization of the north/south gradient of trace gases across the ITCZ; and (3) new particle formation in the outflow of convective systems. The study region was north of Tahiti from approximately 12 to 6 south latitude. Initial results indicate that all objectives were met and expectations for observation of new particle formation were exceeded. Very high concentrations of DMS were observed in the boundary layer on both the north and south side of the ITCZ, along with high concentrations of sulfur dioxide. High concentrations of both of these compounds were also observed in the 15kft to 20kft range, and new particle formation was observed during several encounters with the outflow from convectives systems.

On a more negative note, the P-3B's radome was damaged by the ground tug while positioning the aircraft after the flight. Initial assessment is that the radome can be repaired, and that the capability for the repair is available through Air Tahiti. It is estimated that the repair will take 2 days. The 2nd local flight by the P-3B has been, tentatively rescheduled until Sunday, April 4.

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