You can consider this as a Time Charter In Contract as well. The Head Contract may required for several reasons.

Instead of manual input into the ‘Hire’ field in Estimate (Voyage), with proper setup in Head Contract, the ‘Hire’ field gets automatically reflected with Daily Hire Expenses. Note that 5.0 Financial needs to set up proper in order to reflect the ‘Hire’ field automatically.
To keep track of past/transferred voyages, Delivery, and Redel info operated under the same Head Fixture at 3.0 Voyages
Keep track of all Offhires under the same Head Fixture at 4.0 Offhire
To use the Invoicing feature at 5.0 Financial

Creating of Head Fixture is not compulsory. If managing Time Charter In and Hire Payment is to be handled outside of the VMS system, there may not be a strong reason to rely on the Head Contract feature.

1.0 Creating Head Contract

On the Vessel Register, unlock the lock icon
Click add and a window opens up shown as above.

2.0 Contract

Parties
Fill in the fields accordingly. ‘Owner’ & ‘Broker’ fields are dropdown lists, where options are created from the Company Register.

Remarks
The remarks field here can be utilized to input Head Contract Terms for reference purposes.

C/P Done
Fill in C/P and TC#. These fields are free text and do not generate in-running numbers.
Select the Type of charter from the dropdown list.

Duration
Indicate the Duration which is one of the main terms in a TC Contract. You may input for the Option period as well.

Terms
Delivery Range, Redelivery Range, and Notices are free text fields.

Input the number of days for Redelivery +/- , Option Declare, and Earliest Notice.
Left-click on Estimate Dates to generate the value in Yellow Highlight

3.0 Voyages

Delivery & Redelivery
Input the Delivery & Redelivery details. Take note these are for reference purposes and not used in any Hire Calculation.

Voyages
Any voyages Transferred from the Estimate using the vessel in this Head Contract will be listed here. Below is a sample of how it will look like. The blue hyperlink directs you to the voyage conveniently.

4.0 Offhire

Any Offhire recorded in the Voyage will reflect under this list automatically. In the last row, VMS totals up the total Offhire Days and Offhire Cost.

5.0 Financial

Refer to "TC Out" Voyage as they work on the same logic.

6.0 Linking Head Contract to Estimate/Voyage

--To be continued--