The City of Tshwane has appointed a "transaction advisory" firm to conduct a review into operations at the embattled Wonderboom National Airport.On Thursday, the City announced that the company, Ntiyiso Consulting, had been briefed to review the technical, financial and legal framework of the airport as well as to propose viable funding models for the facility, among other things.This follows reports that the airport was all but collapsing under the weight of allegations of mismanagement.Earlier this month, News24 reported the City's oversight committee on roads and transport had uncovered evidence of not only mismanagement, but corruption and even embezzlement at the airport.Some of the committee's findings were: About R8m and R5m for the construction of a hangar and training centre appear to have been embezzled; R3m was spent on the construction of a lift which never materialised; R800 000 was spent on the construction of a wall which airport management had no clue about; There is no occupational health and safety certificate for the airport; A hangar that was supposed to be for maintenance and used as a depot cannot be used because of bad construction. InvestigationsStarting in January 2020, the "transaction advisory" consultants will assess a wide range of elements pertaining to the airport over a period of two years.According to the City, this mandate included: Drafting of the airport's business plan and ensure alignment with the City's strategic plan and objectives; Attending to labour relation issues; Identifying and addressing capacity gaps; Identifying, evaluating and mitigating potential risks; Addressing the current operational needs and carrying out a benchmarking exercise against other airport operations.But the consultants will not be the first to attempt to rescue the airport.The oversight committee called for a full forensic investigation into Wonderboom. But it now appears as though there have been other forensic investigations, which do not appear to have yielded results. Tshwane MMC for Roads and Transport Sheila Senkubuge said on Thursday there was an internal investigation into Wonderboom and the results were given to the mayor's office in June. These have not been made public.She added the oversight committee's recommendations were noted but were "neither here nor there".Tshwane Mayor Stevens Mokgalapa said on Thursday "some forensic reports" were referred to his office and cases had been opened but some of those who were complicit had died.Senkubuge said the appointment of the "transaction advisory" firm was part of a number of recommendations contained in a report by the University of Pretoria into Wonderboom, which was commissioned in 2016.Private managementThe airport belongs to the municipality but for the past two years, the City has outsourced its management to a private company, Professional Aviation Services (PAS). Concerns from the City's own legal and supply chain management divisions raised concerns about the lawfulness of the appointment, as News24 previously reported, which was extended on a deviation from National Treasury rules recently.Senkubuge said the deviation was to extend the PAS contract already in place. It remains to be seen whether the Auditor-General will agree with this view, and whether it is allowed according to Treasury rules.She added the City would always need external help to run Wonderboom as managing an airport was not part of its mandate or competency.This is despite the fact that the City managed Wonderboom in-house for decades before outsourcing the function in 2017.On Wednesday, the Organisation Undoing Tax Abuse (Outa) called on the City to come clean about allegations that the airport had been mismanaged, and said it must cancel the contract it has with PAS.'Not fit for purpose'Mokgalapa admitted the airport faced serious challenges, making the City question its long-term viability. He added that if it did not become commercially viable, the City would consider the possibility of selling it off."The airport is not fit for purpose," Mokgalapa said. "If it is not commercially viable, I see no value [in it]."He added the City had spent millions on the airport but had received no return on its investment despite the immense potential for economic growth the airport had. Mokgalapa said if Wonderboom could not be saved, the City would begin a public participation process to assess whether the airport should be sold or leased.He added he was "horrified" to discover that the airport posed a national security risk because aircraft were flying in and out daily with no oversight from immigration services.On the side-lines of Thursday's press conference, PAS' managing director, Robert Garbett, told News24 the company had stabilised the airport, saying the Civil Aviation Authority had found 89 instances of non-compliance before PAS was brought in, and many of these had now been fixed.He said there were a number of problems at the airport related to corruption and factionalism for which PAS was not responsible.Mokgalapa defended PAS, saying a plane ferrying guests to the Gupta family wedding, which famously landed at Waterkloof military airport in 2013, initially wanted to land at Wonderboom."If we didn't have a company that could have jammed the signal, [the Gupta plane] would have landed at Wonderboom," Mokgalapa said.