Guidelines : Tethered Balloon System Missions

In a typical year, ARM expects to conduct approximately six to eight tethered balloon system (TBS) missions, using the ARM TBS baseline instruments, with missions taking place over two-week periods. Requests for missions will be made through TBS calls, which will be held near the beginning of the calendar year or through a call for the ARM Mobile Facility (AMF). At this time, TBS missions may only be requested at ARM observatories identified in calls for TBS proposals or as part of AMF proposals.

A standard TBS mission involves a single tethered balloon carrying baseline ARM instruments. In most locations, the balloon must remain in clear air and below the base of nearby clouds. TBS flights are restricted to daytime operations, and an individual flight typically lasts from a few hours to approximately eight hours.

Proposals should provide details regarding mission parameter requirements that may affect science goals. Mission parameters that should be considered include:

• the flight location
• season or seasons
• time of day
• desired altitude
• the number and duration of flights required
• desired meteorological conditions during the flight
• whether fixed-altitude flights or profiles would be more appropriate for their science goals.

Proposals for flights of non-baseline ARM instruments or guest instruments will also be considered but will need to be reviewed in consideration of payload constraints.

In addition, requests may be made to fly guest instruments as part of previously approved TBS missions through the proposal process for small campaigns. Such requests must be submitted in sufficient time for review and integration, but a minimum of four months prior to the campaign depending on the complexity of the instrument and the timing relative to the quarterly review cycle.

Deadlines and requirements for review and approval are based on the type of TBS mission support being requested and proposal level assigned by the ARM Infrastructure Management Board (IMB). Example TBS requests may be to fly a guest instrument on an already planned mission or to plan a TBS mission.

Reviews and decisions on proposals will be conducted on a periodic basis according to the type of TBS support requested and will follow the timeline for levels of small field campaign guidance. Please ensure that the proposed start date of your campaign leaves adequate time for the review and approval process.

Proposals for new TBS missions will be solicited through a TBS annual call. A parallel call is offered in collaboration with DOE’s Environmental Molecular Sciences Laboratory (EMSL) under the Facilities Integrating Collaborations for User Science (FICUS) program, which encourages and enables ambitious research projects integrating the expertise and capabilities of multiple user facilities. The FICUS call offers the same TBS mission opportunities with the addition of particle samplers for offline analysis of aerosol particles at EMSL.

Proposals requesting the particle samplers and EMSL analysis must be submitted to the ARM/EMSL FICUS solicitation. Proposals not requiring the samplers and analysis must be submitted through ARM’s Propose a Field Campaign page.

Please note: The due date to submit preliminary proposals for fiscal year 2026 (FY2026) ARM TBS missions and letters of intent for the FY2026 FICUS call has passed.

While the deadline to request TBS missions in the next fiscal year has passed, small campaigns involving the deployment of guest instruments on a TBS as part of an already approved mission may still be requested. Reviews and decisions on proposals will be conducted on a periodic basis according to the type of TBS support requested and will follow the timeline for levels of small field campaign guidance. Please ensure that the proposed start date of your campaign leaves adequate time for the review and approval process.

• Letters of intent due (required)
• Invitation to submit proposals
• Full proposals due
• Decision notices sent.

Full FICUS Proposal Requirements