Loan investments within Sipps and Ssas

What are the different types of loan investments that are allowable within a Sipp or a Ssas, and what are the key things to be aware of to ensure the transaction is compliant and does not fall foul of the HMRC rules?

A self invested personal pension (Sipp) is a pension vehicle that is established to provide a retirement income for an individual when they choose to retire. However, a true Sipp by its very name is a flexible vehicle, and allows individuals to take control and self invest, this is generally in conjunction with advice from an independent financial adviser. Many pension vehicles are described as Sipps but under close scrutiny do not allow investments in the full range of different opportunities that do exist under the rules and regulations and therefore are nothing more than a personal pensi...